#43 Reflective Shadow Mapping : WIP

- added gbuffer like reflective shadow map writing shaders
- added renderpass for reflective shadow map writing
- added debug view in GUI Frame ( WIP )
- some #28 related changes to shorter path display in AssimpTools and
TextureTools
- fixed uninitialized issue quad pointer in resourcemanager
- added pointer to material textures, to be used for debug view switcher