Working on integrating webgl compositing view into application.
Solved problem of webgl framebuffer contents not getting drawn to canvas.

Canvas is not the same object each time the visualization canvas object's
render method is called.  Therefore we cannot just initialize the webgl
stuff only the first time.  Instead, each time render is called, we need
to delete all the webgl state, and re-initialize everything, using the new
canvas elements generated by the render call.
Integrated real layer selection, working toward final rendering by webgl.

Still not getting zoom or translate callbacks, and not currently drawing
final pass so that aspect ratio of original images is maintained.
Fixed final drawing pass to scale image correctly.

Also brought in glmatrix library for doing vector and matrix math in js
more easily, and added ability to zoom composited image.
Added python and javascript to test two jpg sprites for compositing.
Added one more approach to compositing with webgl.

This time we take in the rgb.jpg and the composite.json as in the standard
javascript approach, then build the png sprite with transparency in the
browser.

Also added some timing instrumentation to all the compositing views.
Cleanup and resolution of many jshint errors, still a few left to figure out.
One more fix to remove final jshint complaints.
Merge branch 'support-webgl-compositing' into merge-support-webgl-compositing

Conflicts:
	web/src/js/app/StandaloneApp.js
	web/src/js/lib/widgets/VisualizationCanvasWidget.js
Fixes to handle changes from fields to controls, as well as pipeline control.
Fixed some bugs introduced by earlier merge with master, removed buttons.

Also hid the fps counts for now, and made a change suggested by Zach.
Merge branch 'master' into merge-support-webgl-compositing

Conflicts:
	Gruntfile.js
	package.json
	web/testing/jshint.cfg
Merge pull request #64 from Kitware/merge-support-webgl-compositing

Merge support webgl compositing