Struct Hiding and GObjectification

by aluink for Pidgin, Finch and libpurple

The first phase of this project will be hiding all purple structs. All struct declarations will be moved into C files and only typdefs will remain in the header files. Accessors will be created to allow access to certain members, while some parts will remain private on purpose. The second half of this project will GObjectify purple. This will entail writing all class and type instantiation code. Refactoring of types will be done where possible using the inheritance aspect of GObjects.