- split addons_gl into basic in addons/gl and new Shapes factory in gl_shapes.rb
- mv drawing modules into their own directory
- remove debug output
- comment
- remove ruby-inline support, which never made it to Ruby 1.9 and is less needed
- split out engine_methods_for_user_object.rb
- engine.rb code reorder
- split up addons_ruby.rb into one file per class/module
- remove ProjectEffectScreenCaptureWithThemeStorage
- remove unused pango tag helpers