Removed useless Roles helper
Added fancy flashes

* Replaced boring Devise flashes with fancy flashes
* Added font-awesome-rails gem for flash dismissing 'X'
Added application access check

* Unless the user is on the root page, they will be checked for
  application access priveleges
* Updated `DapperClient` to deal with lookups on users who are not in
  the `Dapper` user database
* In the future, the `check_access` will be extracted to DapperClient
* In the future, this method will redirect the user to an access request
  page in the Dapper application
Merge pull request #3 from ATNI/checking-application-access

Checking application access