(svn r7565) -Codechange: Rework DEBUG functionality. Look for appropiate debugging levels to
use in debug.h. grfmsg() is now used as a specific debug-function for grf.

(svn r7205) -Fix [FS#350, SF#1560913]: Window allocation and deletion messed with the actual window
structs inside their array, and possibly invalidating pointers higher up.
Meaning that any function called within an wndproc could cause unknown/invalid pointers
once control was returned to this function. Solved by the introduction of an extra
abstraction layer, an array of z-window positions that is only concerned with the
pointers.

(svn r7202) -Codechange: Move _viewports and _active_viewports local to viewport.c and have them
called from the appropiate places in window.c

(svn r7200) -Codechange: remove unneeded redraw (console.c), coding style, use FindWindowById
instead of _windows loop (viewport.c), remove dump-code (mixer.c), MSVC6 borkdness
in stdafx.h, constness (viewport.c), variable localization (win32.c), comments (window.c)

(svn r7094) -Codechange: Get rid of the window-specific code in DoZoomInOutWindow (enable, disable
buttons depending on calling window, game-mode); handle it by broadcasting messages
to the calling window, because that knows how and what buttons to set.

(svn r7047) -Fix [FS#317]: Zooming out near map-borders would previously fail because the new centre
would be outside the map. Change behaviour so that a reasonable approximation is
returned so that zooming (out) still works (GrimRC)

(svn r6884) -Codechange: Add strict bounds checking in string formatting system.
The last parameter should point to the end of the buffer (eg lastof(buf))
Courtesy of Tron.

(svn r6821) -Codechange: For the measurement tool do not show the tooltip when the selection
is only a single tile. Seems this was a bit annoying to some ;)

(svn r6764) -Fix (r6758): Wrong height difference calculated because invalid drag-type
was passed to the function. Thanks peter1138.

(svn r6758) -Feature: Add a measurement tool that will show dimensions and height
differences of various draggable tools (inspiration, concept and double
checking by MeusH).

(svn r6462) -Codechange: Have GetStringWidth() return width as well as the height bounding
box of the string. Therefore rename the function to GetStringBoundingRect()
and have it return a BoundingRect type of width/height

(svn r6368) -Fix [FS#136]: Station catchment area persists after switching tools. The
correct fix was to reset the highlight box if any size changes (grimrc)

(svn r6222) Remove struct ColorList, because the names of its attributes are plain confusing
All the struct holds is a simple colour gradient, so using a simple array with 8 entries is more clear
Also add the names of colour the gradients as enum

(svn r6047) -Codechange: FOR_ALL now _only_ loops valid items, and skips invalid ones
-Codechange: use IsValidXXX where ever possible
Note: both changes to prepare for new pool system, which needs those changes.
For every pool there are 2 ugly lines, which will be removed when done
implementing new pool system.
Based on FS#13 by blathijs, partly implemented.

(svn r6040) -Add: when clicking twice on a Location Button, the SmallMap centers on your position (based on FS#54 by thomasdev)
-Add: when clicking twice in SmallMap on a position, it centers there (based on FS#54 by thomasdev)
-Add: add a button in SmallMap that centers the SmallMap on your current position (based on FS#54 by thomasdev)

(svn r3992) -Fix: Rewrote the code to determine whether a rail-tile can be terraformed.
Fixes a bug where you could terraform a tunnel (fixed by r3228, but reverted that one)
Fixes a bug introduced by r3228 which allowed steep rail tiles resulting in ... unwanted effects such as display artifacts.
That means the terraform feature should not work as intended; it also uses _valid_tileh_slopes to determine valid configurations instead of hand-brewn stuff.
TODO: _terraform_err_tile and similar TileIndices should have INVALID_TILE as "unused", not 0. (0 is a valid tile).

(svn r3254) - Fix: graphical glitch with autorail tool on a certain tile-type.
- CodeChange: adhere the global variables in autorail.h to the coding style (eg. start with underscore).

(svn r3218) -Feature: Multiheaded train engines will now stay in the same train
This means that any user attempt to remove a rear engine will tell the user to move the front engine instead
This fixes the assert when moving multiheaded engines (introduced in r3144)
Note: to make old savegames use this feature, some engines might be turned around in order to link engines in pairs

-Codechange: train subtype is now a bitmask
This allows fast access to info like if it is a wagon or engine and if it is in front and so on
Note: savegame version bump

(svn r3008) [ 1247535 ] Native Support for Win64 (compile&run only) (michi_cc)
Fix warning in graph_gui.c with const problem

(svn r2845) Remove sprite size caching, it was unused
This makes GetSpriteDimension() superflous, because now it's just a thin wrapper around GetSprite() returning only part of the information, therefore remove it too

(svn r2702) -Codechange: Cleaned up the sprite code and replaced many magic numbers
by enums. There remains work in gfx.c to move the "transparency" and
"recolor" bits around to make space for more sprites. However, 2800
additional sprites can now be loaded. There also remains cleanup and
Doxygen work on many of the header files.

(svn r2635) Fix: [ntp/misc] Improve the old pathfinder. Changed it to A* instead of Dijkstra.
- Benchmark shows that NTP is now around 10x faster than NPF.
- Made IsTunnelTile macro to determine if a tile is a tunnel.
- Added some useful debugging functions for making tiles red / getting accurate timestamps.
- Remove old depot finding algorithm.
- Disable warning for signed/unsigned comparisons.

(svn r2595) -Codechange: Introduced "IsSteepTileh" to find whether a tile is steep
(i.e. spans two height levels) and use it throughout the code.
-Codechange: Add CanBuildDepotByTileh to find if a tile is suitable to
build a depot on it. Wraps some bitmagic which seems quite unreadable at
first glance

(svn r2580) Change: Added {INDUSTRY} command for printing industry names instead of the old {TOWN} {STRING} way.
- The formatting of the industry name can be controlled with the string STR_INDUSTRY_FORMAT.
Change: Changed several occurences of {STRING1} into {TOWN} to get rid of townnametype being used directly.

(svn r2440) - Fix: [newgrf] Fix the spritesorter to handle overlapping sprites properly, this fixes display problems with really short wagons. (algorithm by patchman, ported by therax)
- Fix: [newgrf] Too short wagons could break the 'follow next vehicle' code used in the traincontroller. Clamp better to prevent this.

(svn r2046) -Codechange: moved all waypoint code to waypoint.c/waypoint.h
-Codechange: rewrote some functions while moving waypoint-stuff
-Add: added support for 64k waypoints
-Fix: made the waypoint struct a bit more logic (no bit-fucking)

(svn r1894) - Codechange: cleaned up the console a bit, wholly unified handling of text with that of editboxes
- Codechange: Introduction of Textbuf struct which not only holds physical data as length but also pixel-constrains (width) and information about the caret
- Codechange: Move Clipboard function to OS specific file. Currently only Windows has clipboard actions
- Feature: Editboxes, console and exit screen also accept the numeric-enter as a yes
- Feature: Navigation through text with cursor keys is possible, as well as arbitrary insertion (also paste) and deletion; both backspace and del keys. Functions DeleteTextBufferChar, InsertTextBufferChar and InsertTextBufferClipboard handle input and deletion. Navigation is done through MoveTextBufferPos.
- Fix: OTTD crash when opening 'add server' editbox
- CodeChange: fix up some stringwidth calculations in gfx.c. You can get the width in pixels of a character by calling GetCharacterWidth().

(svn r1667) - Feature: Signs are now shown in the color of the player who created them
(Note: The player information is currently not stored in savegames. Upon loading a game the signs will all be gray again)

(svn r1571) Feature: Visually enhanced autorail placing
When using the autorail tool, the rail pieces which are going to be build are highlighted.
If a piece is shown in red, this indicates that the slope/rail combination is impossible. It does not tell you if the rail line construction might not be possible because of other obstacles, e.g. houses or water.

(svn r1486) -Codechange: moved all 'signs' stuff to signs.c/h and prepared it for
dynamic arrays

(svn r1407) -Codechange: changed a lot around _stations, _vehicles, _towns and _industries
(in prepare of dynamic arrays):
- DEREF_XXX is changed into GetXXX
- All direct call are directed via GetXXX
- struct Industry has now an index-field
- ENUM'd some stuff
- Replaced home built loops with FOR_ALL_XXX
- Added _stations_size, _vehicles_size, ... which gives the length of the
array (which will be dynamic in the near future)
- Changed lengtof(XXX) to _XXX_size (e.g. _stations_size)
- Removed all endof(XXX) (because mostly it was part of a FOR_ALL_XXX)
- Made the sort-functions of all 4 dynamic
- Made all 4 Initialize functions more of the same
- Some minor tab-fixing and stuff
(tnx to Tron for proof-reading my 100kb patch ;))

Note for all: please do NOT directly call _stations, _vehicles, _towns and
_industries, but use the right wrapper to access them. Thank you.
Ps: please also do not use 'v++', where v is of type Vehicle *.