Incorporated contribution from pyalot of shader resembling his original one provoking long compilation times with relatively few (<= 256) loop iterations, based on feedback from Nicolas Capens that the original shader's loop count was unreasonably high.
Merge pull request #152 from kenrussell/pyalot_shader

Incorporated contribution from pyalot of shader resembling his original ...
Merge branch 'master' of https://github.com/KhronosGroup/WebGL into polyglot-conform