Add skills and expertise to a person
Add select2-rails to the application

- this will help with the tagging UI
Facilitate tagging without javascript

- if javascript is enabled, remove the form field
and add a hidden field that will be used to cache
the selected tags
Select tags in the profile form with javascript

- this uses the select2 library and proved very
hard to test, so the javascript is untested, though
this should be address at some point
Basic styling for the select2 form helpers
Display skills and expertise on a profile

- capitalise tags before saving the profile
Test the tagging UI with javascript
Person#tag_list returns a string of all tags
Preset the tag_list in the select2 widget

- Person#tag_list is stored in a hidden field

- Ensure tagging.js only executes when #person_tag_chooser is present
Add tags to elasticsearch index
Search by 'tag' from a profile page