Fix inverted mesh rendering

Rendering code for assimp mesh is taken from the examples of assimp (https://github.com/assimp/assimp). There are different use of glEnable(GL_CULL_FACE) and glDisable(GL_CULL_FACE) in the examples. We took incorrect one.
Merge branch 'master'

Conflicts:
	dart/renderer/OpenGLRenderInterface.cpp
Framework for state machine contoller
- This branch will be removed soon