Adding a howto note about sharing the URL

It is displayed if no remote users are present yet.
Adding jshint tool
Extracting inline function from loop
Style fixes
Adding custom (stricter) jshint rules

See http://jshint.com/docs/options/
Code style fixes

Curly brackets are required, some scopes fixed.
Adding csslint tool
Configuring jshint to cover all relevant JS files
Style fixes in server.js

"static" is a reserved word.
Fixing project name also in page heading
Improving release target in makefile

The version in package.json is now automatically updated.
Bump version number for release 0.5.2
Improving makefile: include rebuilding assets

Re-adding explicit check for clean git state
Automated commit of rebuilt assets
Build and updated version number for release 0.5.3