cleanup
using haxe.ds.Vector

--HG--
rename : src/spinehx/Arrays.hx => src/spinehx/ArrayUtils.hx
rename : src/spinehx/SkeletonRenderer.hx => src/spinehx/renderers/SkeletonRenderer.hx
rename : src/spinehx/SkeletonRendererDebug.hx => src/spinehx/renderers/SkeletonRendererDebug.hx