Added new example showing offscreen rendering (GPGPU example here) without any visible window.
Implemented __getitem__ and __setitem__ in ColorArray.
ColorArray.__getitem__ now returns a new ColorArray instance.
Text has point_size and pos properties

And text always draws in that point size, even if inside a viewbox.
Text: can set color, and supply pos and point_size in init
Added assert raise statements in ColorArray tests for __getitem__ and __setitem__.
ModularShader: Fix that program is not recompiled on prepare()

... unless necessary
Address comments
Updated README.
Fixed dash character.
Text: address comments
flake
Added notes about the subpackages.
Added some backends.
Text.pos does not use transform.
Text usable in normal canvas
Merge pull request #404 from rossant/colorarray-indexing

Implement __getitem__ and __setitem__ in ColorArray
Text: addressed comments
Merge pull request #339 from rossant/offscreen-example

Added new example showing offscreen rendering
VNC backend update
- Add IPython DOMWidget to _ipynb_vnc. Now, backend has its own widget to display.
- Edit setup.py, .js files will appear in build.
- No need to write Js code into notebook for event handling.