Fixed integration test to fit new graphics engine. AH-75
Test cases added, added functionality to create textures in Graphics. AH-75
Added support for multiple shader steps to be created simultaneously. AH-128
Fixed some issues with entry points and multiple shader files. AH-75
Multiple changes to graphics engine. AH-75

- Commented graphics engine
- Tested integration of graphics components
- Added model struct in Graphics.h
- Deleted old unused code
- Fixed multiple entry point issues in shader
Small fix to solve testing errors. AH-75