Avatar url field added to user model

External avatar url can now be set from account settings.
Test added for external avatar url field.
Avatar url now accepts empty string
Empty external avatar url is valid value. If user has empty avatar url then gravatar will be used instead.
Minor code formatting
Merge pull request #278 from ar7em/kandan-176-external-avatar

Custom User Profile Pictures
Fixes #285 latest RoR 3.x and devise changes
Update .travis.yml
Update .travis.yml
Merge remote-tracking branch 'upstream/master' into kandan-285

* upstream/master:
  Update .travis.yml
  Update .travis.yml
Merge pull request #286 from fusion94/kandan-285

Fixes #285 latest RoR 3.x and devise changes

tested locally as well.
Adding tests back into Travis
removing tests for now.
Fix layout
Refactor styles and views. Create mobile layout
Optimize for tablet
Optimize for desktop. Improve admin panel and other pages
Fix for mobile
Remove fixed positions. Minor fixes
Merge pull request #293 from mkyurchev/improve-layout

UI improvements **Accepted**
Ensure that kandan is using a version of Devise that supports :token_authenticatable Fixes #295
Fixing the regex in mentions.coffee