oval points
oval radius is min(width, height)
Merge branch 'master' of https://github.com/runrev/livecode into oval_points

Conflicts:
	prebuilt
code cleanup
360 degree ovals
single-quadrant wedges are working
quadrants 2,3,4 working
finally... roundrects, ovals, startAngle, arcAngle
[[ ThreadedRendering ]] Implemented pthread thread pool.
[[ ThreadedRendering ]] Split mac redraws into 4 tiles, each of which is rendered in it's own thread.
[[ ThreadedRendering ]] Initial implementation of windows thread pool.
[[ ThreadedRendering ]] Initial implementation of iOS, Linux and Android threaded rendering.
[[ ThreadedRendering ]] Updated stack tile creation and rendering to platform indapendent level.
[[ ThreadedRendering ]] Put locks around stack id cache access.
[[ ThreadedRendering ]] Fixed minor bug in legacy gradients.
[[ Bugfix 12909 ]] Don't crash on import snapshot
Merge branch 'refactor-syntax_unicode' of https://github.com/runrev/livecode into bugfix-12909
[[ ThreadedRendering ]] Updated Mac platform surface to use single backing buffer.
[[ ThreadedRendering ]] Updated region clipping to make sure all platform stack surfaces clip correctly.
[[ Bug 12250 ]] Hack around bug in NSSavePanel where validateVisibleColumns doesn't work.
Merge branch 'bugfix-12250' into develop
[[ Bug 12819 ]] Check that the stack is keyed in revAvailableHandlers / revAvailableVariables.
Merge branch 'bugfix-12819' into develop
[[ Bug 12946 ]] Stop the sound when asked to or when it finishes playing.
[[ Bug 12945 ]] Problems with tabStops property