Upgrade admin gem to 0.1.0

* Fix broken footer html
* Fix visited link styles on bootstrap components
* Get environment indicator styles
Add custom Transition favicons
Use gem's "link-inherit"

* Replaces the more specific glossary link style
Merge pull request #305 from alphagov/environment-indicator

Show environment indicator
Enable users to select unresolved as a mapping type

- Add a blurb about unresolved mappings and what the point of them is,
  when the option is selected. The copy on this probably needs a work,
  and in fact I'm not even sure it needs to be here. Thoughts?
- Mappings marked unresolved added through here get added, correctly, to
  the database with a type of unresolved.
Add a note explaining what an unresolved mapping is

- The note's copy has been discussed with @fofr.
- Add this as a partial, rendered only when the unresolved dropdown is
  selected, thanks to some JavaScript, and include it in two places.
Show unresolved as archives in the mappings table, in muted style

- Add a question mark with a hover to explain the unresolved type, but
  why it is marked as an archive and greyed out.
- Based on @fofr's prototype.
Show current status when editing unresolved mappings

- Like we do for redirects and archives, and with JavaScript off.
Default mapping type to unresolved in the MappingsFromHostPaths import
Add the ability to filter mappings by type unresolved

- Initially this was a separate story, but given the unresolved
  selection appeared in this story, I thought it sensible to make it
  work. Further parts of the filtering story will be completed in a
  separate pull request.
- Rails was pluralizing "unresolved" to "unresolveds". Tell the
  inflector that "unresolved" is uncountable, so it doesn't do this.
- Unresolved is such a long word, so edit some indentation to line if
  statements up with each other.
Add a count of unresolved mappings to the dashboard

- This is the same as the redirect and archive counts, but it doesn't
  pluralize because we've disabled "unresolved" pluralizing. For
  consistency, and because I couldn't get the `link_to` to work any
  other way, still call `pluralize` in the method to generate the count.
Make the mapping type column in the table slightly wider

- Now, the Archive (?) doesn't wrap.
Refactor two Cucumber steps into one more accurately described one

- Paired with @rgarner.
Show the percentage of unresolved mappings on the dashboard

(Paired with @rgarner on the tests - floating point stuff isn't my
forte.)