Let's use inline checkers in PType instead of constantly having to do clumsy IsKindOf checks etc. Once complete this also means that the types can be taken out of the class hierarchy, freeing up some common names.
Having these two types related can cause problems with detection in the compiler because for some parts they need quite different handling.
Common handling for the fields has been moved into PSymbolTable but overall redundancy was quite minor as both types share surprisingly little functionality.
- added a few access functions for FActorInfo variables.
With PClassActor now empty the class descriptors can finally be converted back to static data outside the class hierarchy, like they were before the scripting merge, and untangle the game data from VM internals.
- keep string registers which are being used as function parameters allocated until after the function call returns. This is for allowing to pass strings by reference which would avoid some costly constructor/destructor loops in the call instruction.
Symbols are very easy to manage once they are in a symbol table and there's lots of them so this reduces the amount of work the GC needs to do quite considerably.
After cleaning out compile-time-only symbols there will still be more than 2000 left, one for each function and one for each member variable of a class or struct.
This means more than 2000 object that won't need to tracked constantly by the garbage collector.
Note that loose fields which do occur during code generation will be GC'd just as before.
