Updated get.webgl.org to recognize the current state of IE and Opera
Re-phrased expermiental support message, removed logic to check for implemented functions
add test cases for drawing the same webgl content to multiple Canvases, including HW accelerated 2D canvas and SW Canvases.
Merge pull request #440 from JunJiang/add-draw-webgl-to-sw-canvas-test

add test cases for drawing the same webgl content to multiple Canvases
Merge pull request #430 from toji/get_webgl_ie11

Updated get.webgl.org to recognize the current state of IE and Opera