Move docs in, from README, and use modern standard form
The default MANIFEST.SKIP includes these, and many others (.git, etc)
Add a basic .gitignore
Use RT 4.0/4.2 static content methods for CSS

The JavaScript contains mason (to decide on M/D/Y vs D/M/Y) and as such
cannot be served from static/ and squished.  The 4.2 solution would be
to place the preference in the JavaScript user configuration hash;
however, this is unsuitable for 4.0.
Update license tags
release 0.21
bump version to 0.22