Merge pull request #25 from rojkov/master

Derived classes must call the base class method geometryChanged() within...
Added QtMozEmbed event loop implementation which allow run embedding in Async mode
Make sgnode SetViewIsActive thread-safe
Make Invalidate/update thread safe from Qt perspective
Make it enable HW accelerated context with GLX backend
Create Qt and Geck render thread objects
Updated
Created special objects which would help to composite gecko across different threads
Make requestGLContext more thread safe
Make Rendering don't crash if requested in different thread
Run Accelerated rendering for Qt5 by default always
Make it finally render in different thread
Make Qt Render thread join into Main thread and render with Gecko compositor
Safe implementation of Gecko compositor in Main Qt thread working with QtRender thread
Fixed rendering with Gecko Compositor in separate thread
Removed QML_BAD_GUI_RENDER_LOOP from tests runner
Make QOffscreenSurface as fallback plan if reusing Qt render thread surface for another QGLContext failed
Added Implementation for rendering via FBO ( but it does not work yet by some unknown reason :( )
Removed wrong include
Implemented rendering using Gecko CompositeSurfaceTarget Wrapper, make it finally kinda work on multi thread render setup