Native function output arguments

[lgrahl]

Some native functions like PLAYER::GET_PLAYER_RGB_COLOUR store the output values in the passed arguments using pointers. Fortunately, there are not many functions that behave in this manner. SWIG has a solution for this (called typemaps). However, there are some problems:

• The typemaps need to be defined manually in natives.i
• A typemap applies to all functions that have arguments with the same name and type
• There are no predefined typemaps for custom types (but they all use integers internally, so this shouldn't be a big problem)
• Parameter names in natives.h will change in the future

If you find a native function that has not been covered by the currently defined typemaps, please fix natives.i directly or add a comment here.