Add test coverage

clean readme

Feature/fix readme

…ere were errors with uncompressed and closure directory locations

Also removes checkout of development branch from instructions since github provides the default branch automatically.

Fix readme instructions

Code deploy

Uses slackin hosted on a little Heroku app.

It has css warnings that cause problems with whitenoise in production. If developers need it to use uncompressed blockly, they can pull it down.

Points chat link to public gateway to our slack

…subrepos

…lly_pull_subrepos

Code deploy must manually pull subrepos

…ome_page

Adds descriptive content to home page

Fixes centering of footer at small screen sizes