Add QuadSplitScreen effect

New QuadSplitScreen effect, 4 regions of the screen can 

• QuadSplitScreen-1-0-0.c3addon: C3, zoom 4 regions of the screen into four quadrants of the screen for a single layout Quad Split Screen effect. Parameters to control zoom and offset per window.
• QuadSplitScreenExample-1-0-0.c3p: C3 example (based on Eat 'Em Up example project.)