Added framerate limit control
Added class and structure for Shaders
Reorganzied internal shader system

Split up into BurnShaders which just handles all internal shaders and
Shader which handles one single type of shader and its parameters
Added new class ReferenceCounter for tracking references
Added missing destructor for ReferenceCounter & GlEntity derives it
Unfilled function prototypes for Shader
Implemented some methods for a simple shader load
Shader can be loaded. Needs tons of improvement. Check shutdown stall (mb. context)
Temporary: Some debug information for fixing shutdown stall

Burngine needs advanced error handling and has to test every possible
failing action. Implementing next...
Implemented error logger with execution abort
Corrected comments
Error outputs source file and line number
Shaders are now internal-only (::priv). Fixed shutdown stall. Added strict exception handling

Currently only Windows has all these features. Tested on MinGW only.
Platform ports should be done soon. No MacOS support at all...
Enhanced Error Reporting on Windows!
Cropped file to necessary path
Added namespace indention
Added little comments
Exported func implementations to clean header file
Removed logging
Encapsulated shader load and release a little more