Codechange: Redefine some cargo-related values in terms of CargoID instead of CargoType.

Values used as special filter types are now defined as offsets from NUM_CARGO instead of confusingly reusing CARGO_NO_REFIT/CARGO_AUTO_REFIT types.

Cleanup: Remove some unused functions. (#11429)

These were picked up with cppcheck.

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: remove the special station/vehicle code from SaveLoad

With the new SLEG_STRUCT it is much easier to embed a struct
in a struct, where the sub-struct has limitations on when it is
being used.
This makes both the code easier to read (less magic) and avoids
the SaveLoad needing to know all these things about Stations
and Vehicles.

Codechange: C++-ify lists for SaveLoad (#9323)

Basically, this changes "SaveLoad *" to either:
1) "SaveLoadTable" if a list of SaveLoads was meant
2) "SaveLoad &" if a single entry was meant

As added bonus, this removes SL_END / SLE_END / SLEG_END. This
also adds core/span.hpp, a "std::span"-lite.

(svn r16338) -Codechange: split loading of references to two phases
In the first phase, indexes are stored. In the second phase, indexes are checked for validity and converted to pointers

(svn r16199) -Codechange: Pass OrderNonStopFlags also to MakeGoToDepotOrder().
-Fix: 'Go non-stop to nearest depot'-orders did not work wrt. the 'non-stop' part.
-Fix: Adding 'Go to nearest depot'-orders did not respect the default setting for 'non-stop'.

(svn r12648) -Feature: allow four different non-stop types in a single game instead of two. The "TTDP compatible order" setting now only sets the default behaviour of new trains.
-Feature: allow three different load type in a single game instead of two. One can choose full load all and full load any instead of full load being governed by the "full load any" patch setting.