Add explicit interface to switch between OpenGL contexts (refs #203)
Make glowwindow and glowutils optional
Remove glowutils dependency of glowwindow
Merge branch 'master' into explicit_context_switch
Merge branch 'master' into optional_glowwindow_and_glowutils
Merge branch 'master' into optional_glowwindow_and_glowutils

Conflicts:
	source/CMakeLists.txt
Merge branch 'master' into explicit_context_switch
Refactor debug message output to use context registry specific implementations
Merge remote-tracking branch 'origin/master' into debug_output_refactoring

Conflicts:
	source/glow/CMakeLists.txt
	source/glow/source/debugmessageoutput.cpp
Merge pull request #214 from hpicgs/debug_output_refactoring

Refactor debug message output to use context registry specific implement...
Fix CMakeLists for glow
Merge pull request #211 from hpicgs/explicit_context_switch

Explicit context switch (closes #203)
Fix setDrawBuffers methods
Wrap flushmappedbufferrange (refs #165)
Add bindless versions of setting read and draw buffer(s)
Fix framebuffer blitting
Fixes windows bugs

* dllimport functions may NOT be defined in headers
* msvc thinks const is SUPER important
Merge pull request #215 from lordgeorg/master

Fixes windows bugs
Fix ref_ptr to const types (closes #176)
Merge branch 'master' of github.com:hpicgs/glow