Blender Git Loki

Improvements to the Freestyle Python API (needed by the SVG Exporter)

This patch adds some new functionality to the Freestyle Python API, notably:

- MaterialBP1D, checks whether the supplied arguments have the same material
- Fixes a potential crash in CurvePoint.fedge (due to NULL pointer)
- Makes (error handling in) boolean predicates more robust
- Adds a BoundingBox type, to make working with bounding boxes easier
- Adds several new functions (get_object_name, get_strokes, is_poly_clockwise, material_from_fedge)
- Adds a StrokeCollector StrokeShader, that collects all the strokes from a specific call to Operators.create()
- Adds hashing and rich comparison to the FrsMaterial type

These new features (most of them, anyway) are needed for making a more robust SVG exporter that supports holes in fills.

Reviewers: kjym3, campbellbarton

Subscribers: campbellbarton

Projects: #bf_blender

Differential Revision: https://developer.blender.org/D1245