This is to block modification of the planes directly. For future-proofness with renderer changes everything that alters these values should go through he function interface.
- do not resolve the backdrop texture to a texture ID at load time. This will allow custom menu classes to use this info differently.
- added a new ZSDF userstring property to dialog pages to give mods more means for customization.
- allow overriding the conversation menu class both globally through MAPINFO and per conversation in ZSDF.
This required splitting A_CallSpecial into a direct wrapper around P_ExecuteSpecial and implementing itself as a script function calling ExecuteSpecial so that this special case can use a version of the function that can be used without an activator.
This also means that the remaining scriptification of the menu is on hold. The player menu would require even more access to critical game data, which is a no-go, and the other remaining menus offer little benefit from getting scriptified.
Making this an object had little to no advantage, except being able to remove the deleter code. Now, with some of the class data already being allocated in a memory arena so that freeing it is easier, this can also be used for the drop item lists which makes it unnecessary to subject them to the GC. This also merges the memory arenas for VM functions and flat pointers because both get deleted at the same time so they can share the same one.
If a later module reused an existing name for a different class or struct type, this new name would completely shadow the old one, even in the base files.
Changed it so that each compilation unit (i.e. each ZScript and DECORATE lump) get their own symbol table and can only see the symbol tables that got defined in lower numbered resource files so that later definitions do not pollute the available list of symbols when running the compiler backend and code generator - which happens after everything has been parsed.
Another effect of this is that a mod that reuses the name of an internal global constant will only see its own constant, again reducing the risk of potential errors in case the internal definitions add some new values.
Global constants are still discouraged from being used because what this does not and can not handle is the case that a mod defines a global constant with the same name as a class variable. In such a case the class variable will always take precedence for code inside that class.
Note that the internal struct String had to be renamed for this because the stricter checks did not let the type String pass on the left side of a '.' anymore.
- made PEnum inherit from PInt and not from PNamedType.
The old inheritance broke nearly every check for integer compatibility in the compiler, so this hopefully leads to a working enum implementation.
- improved the class pointer to string cast to print the actual type it describes and not the class pointer's own type.
- fixed: The 'is' operator created non-working code when checking the inheritance of a class pointer, it only worked for objects.
