Integrated the jquery lib select2 (http://ivaynberg.github.io/select2/)
via the select2-rails gem. It will provide a nice autocomplete tagging
experience.
bootstrap.js.coffee is causing JS errors because the bootstrap js
files aren't included in the page. As the selectors in it don't match
any DOM elements it should be safe to remove that file.
Using the jquery lib select2 in tags mode to have tag auto-completion
and selection from the pool of already used tags.