Cleaned up debugging the sample scripts.
cleaned up debug drawing code in the skinning modifier.
added debug drawing to the blend shapes modifier.
Fixed bugs in OGLVertexColorOverlayShader and added as 'OGLVertexColorOverlayShader2' to RiggingToolbox. (This shader should be removed when 1.14.2 is released)

Updated the SkinningModifier and the BlendShapes modifier to use OGLVertexColorOverlayShader2