Revert: Build signals to the next junction when dragging regardless of the Ctrl state (#12034)

This reverts commit b370ae1212abdc97034a6b4b8a2dffcffa1911f0.

Codechange: Add base() method to StrongType to allow access to the base type without casting. (#11445)

This removes the ability to explicitly cast to the base type, but the requirement
to use .base() means the conversion is still explicit.

Codechange: Use std::copy/fill pattern to initialize rail and road specs. (#11285)

This avoids use of lengthof and array indices.

Codechange: make explicit when a TileIndex is cast to its basetype (#11190)

This prevents people accidentially assigning a TileIndex to a Date
or any other type they shouldn't.

Codechange: automatic adding of _t to (u)int types, and WChar to char32_t

for i in `find src -type f|grep -v 3rdparty/fmt|grep -v 3rdparty/catch2|grep -v 3rdparty/opengl|grep -v stdafx.h`; do sed 's/uint16& /uint16 \&/g;s/int8\([ >*),;[]\)/int8_t\1/g;s/int16\([ >*),;[]\)/int16_t\1/g;s/int32\([ >*),;[]\)/int32_t\1/g;s/int64\([ >*),;[]\)/int64_t\1/g;s/ uint32(/ uint32_t(/g;s/_uint8_t/_uint8/;s/Uint8_t/Uint8/;s/ft_int64_t/ft_int64/g;s/uint64$/uint64_t/;s/WChar/char32_t/g;s/char32_t char32_t/char32_t WChar/' -i $i; done

Codechange: pass "ground vehicle" to GetTileSlopeZ since for tunnel/bridges there are two states

Previously it checked the position in non-driving direction to "guess" whether
a ground vehicle was using the function, so on tunnels/bridges it could either
return the Z of the (virtual) ground compared to the Z of the path the vehicle
would take.

Fix #9869: remove docking tile when doing a clear square

Terraforming through objects placed on water didn't properly remove docking tiles as expected.

By moving some logic regarding removal of docking tiles into DoClearSquare, the issue is solved, while also simplifying code, avoiding repetition elsewhere.

Codechange: Template DoCommand to automagically reflect the parameters of the command proc.

When finished, this will allow each command handler to take individually
different parameters, obliviating the need for bit-packing.

Codechange: Let the compile generate the master command table out of templated command traits.

This is using a non-intrusive type-traits like templated system, which
allows compile-time validation that the command table and the command
enum match up.

Codechange: DC_NO_RAIL_OVERLAP is a remnant of the OldAI. (#8496)

The OldAI was removed in 2009. Pretty sure we can remove this flag
now too.

Fix #6407: Show snowy ground sprites for depots (#7671)

This is a quick fix by @KeldorKatarn:
https://github.com/KeldorKatarn/OpenTTD_PatchPack/commit/65e656b9d6b24476d074ec6b41830a8f197d535b

It has the drawback that snow is draw to the inside the depots as well, as the removed comment suggests.