Codechange: Rename TownEffect to TownAcceptanceEffect.

This makes it clearer that TownEffect only affects acceptance behaviour.

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.

Codechange: Split CT_INVALID into CT_INVALID and INVALID_CARGO.

INVALID_CARGO is a CargoID and should be used for most purposes in game.
CT_INVALID is a CargoType used for defining default properties.

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

Add: [Script] ScriptCargo::GetName, to get the human readable name of a cargo (#8544)

Of course this translates into AICargo.GetName() for AIs and
GSCargo.GetName() for GameScripts.