Moves desc attributes into a single base class
Better name for AscDescBase
Moves all tests for desc attribute into dedicated AscDescBase test block.
Adds AscColorSpaceBase class for input and viewing desc.
Updates tests. Adds hasattr tests to subclasses to make sure they subclassed correctly. Adds super() to base classes to help with multi subclassing.
Changes how desc behaves- now makes list/tuples replace. None clears. Returns list.
Updates docs with new classes and behaviors.
Includes new classes in __all__ export
Revised parse_cc to be schema compliant. TESTS NOT UPDATED.