Added Color class.
Added Brush class, Canvas class and DrawTriangle{s} functions.
Added Image class. Added SetSourceTo* functions to Brush.
Added SaveImageToStream function.
Image now inherits from Canvas.
Changed drawing algorithm to use integers and scanlines.
Vertical coordinate is now clamped when drawing.
Initial commit for UI.
Added drawing function for views.
Pixmaps are now freed.
Pixmap is now reallocated lazily.
Views are now only redrawn as needed.
Updated TODO.
Expose events are now combined.
ViewCanvas now asserts rows are in bounds.
Added XLib/OpenGL backend.
Suppressed warnings.
Added UniformColorBrush.