Add simple generator for generic types
Add Parameter class (does not compile)
Make GLenum strongly typed
Merge remote-tracking branch 'origin/master' into arguments_callback

Conflicts:
	source/glbinding/source/extension_requirements.cpp
Prepare for parameter callbacks
Add dynamic template parameter subclass
Rename Parameter to Value and add callback for return value
Add callbacks example
Make enum type safe via struct instead of enum class
Merge remote-tracking branch 'origin/master' into arguments_callback

Conflicts:
	source/glbinding/include/glbinding/constants.h
	source/glbinding/source/constant_names.cpp
	source/glbinding/source/declarations.h
Remove debug output
Split maps in single files
Add APIENTRY to types.h
Add explicit function list of all known functions (refs #6)
Improve callback level setter interface
Fix callback level bitmasks
Add lazy initialization (refs #3)
Merge pull request #9 from hpicgs/arguments_callback

Arguments callback (closes #3, closes #6)