This avoids specializing CSingleton<T>::m_instance for each type, and
instead just defines it once in the header. This is allowed by the
standard, multiple definitions are merged in the same way that inline
functions are.
* removed classes managed by CInstanceManager
except for CObject, CPyro, CBrain and CPhysics
because of dependencies
* refactored instance searching to use existing singleton instances of
CApplication, CEngine and CRobotMain and calling their getter
functions
- fixed model loading code
- added simple model viewer (model_test) in src/graphics/opengl/test
- added system time stamp code
- split the code in app/system modules to separate headers
- added debug messages in model loading
- minor fixes in OpenGL engine