Update README
Provide a more Buildbox-like local environment. Clean out unused crap.
Use CSS from Buildbox
fallback to a dev selector if prod src tag is not present
Merge remote-tracking branch 'origin/master' into buildbox-like-sandbox

Conflicts:
	README.md
Update README.md
Merge pull request #31 from envato/buildbox-like-sandbox

Buildbox-like sandbox