GL_KHR_debug
http://www.opengl.org/registry/specs/gl/KHR/debug.txt
GL_KHR_debug
	GL_CONTEXT_FLAG_DEBUG_BIT 0x00000002
	GL_STACK_OVERFLOW 0x0503
	GL_STACK_UNDERFLOW 0x0504
	GL_DEBUG_OUTPUT_SYNCHRONOUS 0x8242
	GL_DEBUG_NEXT_LOGGED_MESSAGE_LENGTH 0x8243
	GL_DEBUG_CALLBACK_FUNCTION 0x8244
	GL_DEBUG_CALLBACK_USER_PARAM 0x8245
	GL_DEBUG_SOURCE_API 0x8246
	GL_DEBUG_SOURCE_WINDOW_SYSTEM 0x8247
	GL_DEBUG_SOURCE_SHADER_COMPILER 0x8248
	GL_DEBUG_SOURCE_THIRD_PARTY 0x8249
	GL_DEBUG_SOURCE_APPLICATION 0x824A
	GL_DEBUG_SOURCE_OTHER 0x824B
	GL_DEBUG_TYPE_ERROR 0x824C
	GL_DEBUG_TYPE_DEPRECATED_BEHAVIOR 0x824D
	GL_DEBUG_TYPE_UNDEFINED_BEHAVIOR 0x824E
	GL_DEBUG_TYPE_PORTABILITY 0x824F
	GL_DEBUG_TYPE_PERFORMANCE 0x8250
	GL_DEBUG_TYPE_OTHER 0x8251
	GL_DEBUG_TYPE_MARKER 0x8268
	GL_DEBUG_TYPE_PUSH_GROUP 0x8269
	GL_DEBUG_TYPE_POP_GROUP 0x826A
	GL_DEBUG_SEVERITY_NOTIFICATION 0x826B
	GL_MAX_DEBUG_GROUP_STACK_DEPTH 0x826C
	GL_DEBUG_GROUP_STACK_DEPTH 0x826D
	GL_BUFFER 0x82E0
	GL_SHADER 0x82E1
	GL_PROGRAM 0x82E2
	GL_QUERY 0x82E3
	GL_PROGRAM_PIPELINE 0x82E4
	GL_SAMPLER 0x82E6
	GL_DISPLAY_LIST 0x82E7
	GL_MAX_LABEL_LENGTH 0x82E8
	GL_MAX_DEBUG_MESSAGE_LENGTH 0x9143
	GL_MAX_DEBUG_LOGGED_MESSAGES 0x9144
	GL_DEBUG_LOGGED_MESSAGES 0x9145
	GL_DEBUG_SEVERITY_HIGH 0x9146
	GL_DEBUG_SEVERITY_MEDIUM 0x9147
	GL_DEBUG_SEVERITY_LOW 0x9148
	GL_DEBUG_OUTPUT 0x92E0
	void glDebugMessageCallback (GLDEBUGPROC callback, const GLvoid *userParam)
	void glDebugMessageControl (GLenum source, GLenum type, GLenum severity, GLsizei count, const GLuint* ids, GLboolean enabled)
	void glDebugMessageInsert (GLenum source, GLenum type, GLuint id, GLenum severity, GLsizei length, const GLchar* buf)
	GLuint glGetDebugMessageLog (GLuint count, GLsizei bufsize, GLenum* sources, GLenum* types, GLuint* ids, GLenum* severities, GLsizei* lengths, GLchar* messageLog)
	void glGetObjectLabel (GLenum identifier, GLuint name, GLsizei bufSize, GLsizei* length, GLchar *label)
	void glGetObjectPtrLabel (void* ptr, GLsizei bufSize, GLsizei* length, GLchar *label)
	void glObjectLabel (GLenum identifier, GLuint name, GLsizei length, const GLchar* label)
	void glObjectPtrLabel (void* ptr, GLsizei length, const GLchar* label)
	void glPopDebugGroup (void)
	void glPushDebugGroup (GLenum source, GLuint id, GLsizei length, const GLchar * message)
	typedef void (APIENTRY *GLDEBUGPROC)(GLenum source, GLenum type, GLuint id, GLenum severity, GLsizei length, const GLchar* message, GLvoid* userParam)
