Implement weak referencing for subscriber info using c-api
PreProcessor Directive indentation
Allow explicitly setting ShaderUsage==FULL on Macs with Intel graphics.
Throw an exception in Publisher::subscribe if callable parameter is neither a callable nor None.
Document Publisher.subscribe() behaviour if callable == None
Documented Point2D.angle(p1, p2) (Fixes #508)
Test (fails) for crash in TransformRecognizer.
Fix crash in TransformRecognizer if Node is unlinked but not deleted.
Merge pull request #519 from libavg/bugfixes/transform_recognizer

Fix crash in TransformRecognizer if node is unlinked but not deleted.
Add sample for textured lines.
Added polyline to lines sample.
Fixed texture coordinates for textured lines.
Merge pull request #520 from libavg/bugfixes/texcoords

Add textured line sample; fix texcoords for lines.
Added test for TransformRecognizer abort during up with inertia.
Fixed #518: Calling abort() during onUp() in TransformRecognizer with inertia caused a crash.
Merge pull request #515 from libavg/features/c-api-subscribers

Features/c api subscribers
Merge branch 'master' into features/automatic_plugin_registration
Add legacy registerPlugin support