Moved engine module from addons to harmony.
Merged clear_area method into rasterize method in Shadeless.
Moved two OpenGL function calls to prepare_buffers method in
Shadeless.
Simplified create_element in Shadeless.
Reordered initialization of Shadeless.
Merged OpenGL initialization functions in Shadeless.
Simplified glsl programs and shaders initialization functions
in Shadeless.
Removed uneeded arguments from Shadeless.
Moved rasterizer module into window module.
Moved GLFW initialization from Window to Engine.
Grouped window creation parameters into a tuple.
Renamed initialization_* methods to init_* in Shadeless.
Renamed initialization_* methods to init_* in Window.
Renamed setup_logging to init_logging in Engine.
Moved exit key registration from Engine to Window.
Changed handling of window should_close in Engine.
Added logging message to escape key handler in Window.
Added comment to title property of Window.
Renamed load_files to init_blend_files in Engine.
Moved physics module into database module.