from Luca Bonavita (mindrones) - adds the method "rebuildProxy()" useful to rebuild all the strips at once: the user can do - adds a BlendModes dictionary under the Blender.Scene.Sequence module: the user can see the blending option with - adds the getter/setter "blendMode" - adds a function seq_can_blend in sequence.c as requested by Peter, useful for these purposes but also to solve a bug after - the bug is you can apply blend modes to an audio strip that doesn't make sense: changed the test and now you cannot assign blend mode other than Replace to audio strips Omitted DNA cleanup part since its only whitespace and Id prefer to have a useful "svn blame" output.