Edit images with jspaint in Atom.

Currently supports the following file extensions:

• .gif
• .ico
• .jpeg
• .jpg
• .png
• .bmp

Use paint:new for a blank canvas.

Check out the paint: in the command palette for more commands. The editor doesn't take focus automatically yet, so you'll have to click on the status bar for the commands to be available.

• Load images (this commit broke some things with security errors, but that should be fixed with a local copy of jspaint)
• Use git submodule for jspaint
• Serialization (using data: URIs)
• Save images (by reverse engineering)
• Commands (more commands... paint:toggle-toolbox, etc.)
• Hide menus (most of them don't work in Atom, a bunch aren't wanted, and we can already have discoverability (via the command palette) without a second menu; this is an embedded editor after all, not a full-fledged application)
• Status bar integration
• Theme integration

I should write specs...