Added clear() function to TriangleStrip.as
Merge pull request #87 from SamHellawell/patch-1

Added clear() function to TriangleStrip.as
Adding clear to TriangleFan

Following Sam Hellawells patch, the TriangleFan also get a clear method.
The clear method now also includes a call to setGeometryInvalid.
Removing Function pointers in Stroke

The use of Function "pointers" for Math.sin and Math.sqrt proved very
costly. Removing them in the calculations speeds things up quite a bit.
Removing Function pointers in CurveUtil

Removing calls to frequent math functions through Function variables, to
gain a significant boost in math performance.
Adding a set of performance improvements

After some Scouting, adding these fixes to boost performance when adding
vertices and generating the Stroke geometry. A heavy test case went from
8,4 to 10,6 FPS on my machine.
this commit is related to the same issue as for the one from 29. November 2013 15:57:40.
In short, it makes it possible to test classes that use graphics extension.