Blender Git Loki

soc-2008-mxcurioni: added Iterator class, base class for all iterators in Freestyle (on the C++ side). Created the equivalent in Python BPy_Iterator with the simple interface:
- getExactTypeName()
- increment()
- decrement()
- isBegin()
- isEnd()

Contrary to previously stated, I am reverting back to implementing iterators in the (Python) API, for different reasons:
- it will make testing quicker to achieve, as I won't have to recode a big chunk of the original Python files
- it will be a base for API refactoring
- it won't prevent the use a list-based approach later (it is simple to get it from the Iterator)