(svn r16694) -Fix [FS#2995] (rgradual loading, rnewindustries): only pay for whatever has been actually unloaded and perform the payment when unloading has finished. This fixes, amongst others:
* cheating by starting to unload and after getting paid rushing to the depot to get sold (or unloading, loading and getting paid again for the remainder)
* cargo being dropped onto a station at the moment a stockpiling industry doesn't accept it anymore
* industries getting cargo that has not been unloaded yet and subsequently dumping it back on the station in one go
Note: you will now get paid after the unloading has finished, so you'll have to wait a bit longer for 'your' money.

(svn r14306) -Codechange: unify the code to draw the vehicle list.
-Fix [FS#2292]: inconsistency between drawn vehicle lists in the vehicle list and group windows.

(svn r14125) -Fix [FS#2237]: Segfault when autoreplace failed very early.
Note: Proper indenting in next commit.

(svn r13002) -Fix (r13001): [autoreplace] previous fix broke updating of a pointer to the front vehicle in certain cases
Now it's updated when it's the front vehicle and it's every time it's the front vehicle and only if it's the front vehicle (nomatter if the replacement works or not)

(svn r12913) -Add: ability to backup and restore a player's economic data and data for a vehicle (or chain of vehicles)
Autoreplace uses this with the following benefits:
-Mass autoreplace (the button in the depot window) will now estimate costs correctly
-Autoreplace now either replaces correctly or manages to keep the original vehicle (no more broken trains)
Thanks to Ammler for testing this

(svn r12792) -Codechange: [autoreplace] added a function to figure out if a replacement is needed and if so, to which EngineID
It's designed to save a bit of CPU time, specially if the replacement isn't buildable (think autorenew of old vehicle)

(svn r12791) -Codechange: [autoreplace] Added a flag parameter (listens for DC_EXEC and DC_QUERY_COST) and included more info when returning CommandCost
This allowed cleaning up the code in MaybeReplaceVehicle()

(svn r12421) -Feature: [autoreplace] the autoreplace button in train depots will now also replace wagons even if they aren't connected to a locomotive
fixed estimated cost in CmdDepotMassAutoReplace() (will still not estimate wagon removal profits)
Made it possible to command CmdDepotMassAutoReplace() to either replace everything or nothing (the button will still happily replace just some of the vehicles if cash premits)

(svn r12230) -Codechange: [autoreplace] made a function to detect if a vehicle needs autorenewing
This will remove duplicated code and ensure that the check is consistent

(svn r11929) -Fix (r9981)[FS#1624]: [autoreplace] fixed a case where a single headed locomotive caused an assert when being replaced to a dualheaded one
This triggered if the player had enough money to replace and refit one of them but not enough to refit the last one as well

(svn r11928) -Fix (r6393): [autoreplace] autoreplace could refit train engines to the wrong cargo type if the old engine had no cargo capacity and the new one had
Now autoreplace will always look at the wagons to figure out what to replace to (as originally intended)

(svn r11822) -Codechange: Replaced fixed size custom name array. Names are now attached to their object directly and there is
no limit to the amount of names.
-Fix: NewGRF engines could not be renamed.

(svn r11044) -Fix (r11043): [autoreplace] a proper fix should cover all cases, not just the one mentioned in the bug report
Certain dualheaded/articulated consists could still trigger this issue

(svn r11011) -Fix [FS#1129]: GetFirstVehicleInChain did change the game state while being marked const.
-Codechange: do not brute force determine the first vehicle in the chain or previous vehicle, but do it by properly accounting the previous and first pointers when updating the next pointer. This gives a performance increase of about 15% when there are a lot of vehicles in the game.

(svn r9981) -Fix: fixed a rare event that could cause autoreplace to run out of money and generate an error (spotted by elmex and UndernotBuilder)
This happened if the new engine was a dualheaded engine and there was money to replace and refit the front, but not the rear
It also adds the cost of refitting the rear end of dualheaded engines to the cost animations (display only)

(svn r9967) -Fix (r9938): autoreplace would in certain conditions move dualheaded engines in a train (usually to the rear)
-Change: moving an engine in between the two ends of a dualheaded engine will now move the rear dualheaded engine to the front of the newly added engine (instead of moving the new engine to the rear of the rear dualheaded engine)
This can make a difference if there are wagons in the train

(svn r9938) -Fix [FS#799]: 100 wagons train + replace engine
Replacing a unit in a train will now remove the old unit before adding the new one. This will solve issues when max train length has been reached

(svn r9753) -Fix [FS#732]: trains are lost after autorenewal/autoreplace
v->dest_tile is now copied when replacing the front engine