* add QualifiedName to VMFunction and allocate these static names from the class data memory arena instead of using FStrings.
* null pointer type checks in the VM added to avoid crash on bad codegen.
Due to C++ conversion rules this was a bit too volatile. There's really not enough places where being able to pass a string directly into the sound API was beneficial - the two most frequent functions now got overloaded variants.
* removed refreshFreq variable and related code. This only got into the backend because of stupid interpolation code in some of the Build games which has long been removed.
* save FixedBitArrays as base64 in savegames.
* allow indirections in the string table - by prefixing the language string with '$$' the remaining text is interpreted as another string label to resolve.
* constexpr in palette code, also replacing #defines with enums.
If the loader is allowed to go on, these objects will be linked into game structures and may do unpredictable things before the loader has a chance to abort at the end.
