This adds:
* builtin types color, state and sound.
* ending a parameter list with an ellipsis to declare a varargs list. (A_Jump uses this.)
* allowing to declare optional arguments by giving them a default value.
* adding an 'action' qualifier for function declarations.
- fixed: The tree nodes for classes and struct members were stored in the global tree nodes table.
- sort variable declarations into their own list for processing.
This uses a different algorithm as the old implementation - instead of recursively resolving unknown symbols it will first collect all constants from all scopes and then process them in one operation, doing multiple passes over the list until no more constants can be resolved anymore.
