Fire NProgress on User, Post, and Settings save

Closes #3037
- Created `NProgressSaveMixin`, which extends the `save` method of a model
  to fire NProgress.
- Extended `UserModel`, `PostModel`, and `SettingModel` with the new
  mixin.
- NProgress can be disabled by passing an options hash to the save function with the `{disableNProgress:true}`
- Now that the ValidationEngine isn't the only thing playing with options inside of `model#save`, refactored it to pass the options down the super chain.
Some sweets for my sweets
Merge pull request #3263 from joshk/patch-1

Some sweets for my sweets
sugar for my sugar
Merge pull request #3265 from joshk/patch-2

sugar for my sugar
Add status invited-pending for users

no issue
- added status invited-pending for invited users where sending the
invitation email failed
- removed console.log() from authentication.js
Add bower to travis cache
Merge pull request #3212 from novaugust/nprogress-save

Fire NProgress on User, Post, and Settings save
Merge pull request #3260 from sebgie/invited-pending

Add status invited-pending for users
Update Ghost-UI version to ~0.8.0

No issue

- Changes Ghost-UI version to look for any version from 0.8.0 onwards.
Merge pull request #3267 from ErisDS/cache-bower

Add bower to travis cache
Merge pull request #3268 from PaulAdamDavis/bower-ghost-ui-080

Update Ghost-UI version to ~0.8.0
Upgrading bookshelf to 0.7.6 & knex to 0.6.21
Settings: Admin User Tab

closes #2422

- updated to use new change password method
- have all save settings use notifications
- create assetUrl helper for creating asset paths with subdir's properly
 prefixed
- move all url based helpers onto a url object in ghost-paths
Refactoring fixtures

refs #2600, refs #2379

Refactoring fixtures to make permission management a little easier
- Separate fixtures into JSON file and split permissions fixtures from other fixtures
- make fixture migrations more robust by fetching objects, not relying on
  ids and checking before adding
- changed owner fixture slightly to remove any confusion between the 'Owner' role and 'Ghost Owner' user.
- moved 003 fixture versions out of config into logic, possibly not a good
  idea
- refactored permissions fixtures and added permissions_roles fixtures to
  make it easier to read / add
Merge pull request #3253 from hswolff/settings-user-tab

Settings: Admin User Tab
Merge pull request #3238 from ErisDS/issue-2600

Refactor fixtures & fixture migrations to 003
Refactor settings routing and mobile interactions

Closes #3254, closes #3138, closes #3245
 ### Settings Routing and View refactoring
- Refactored `SettingsView` to handle transitions between mobile and desktop layouts
- `SettingsRoute` will only transition to `settings.general` if the screen is large enough to show both the menu and the content
- Added `SettingsIndexView` to handle showing the settings menu on mobile screens
- Added `SettingsContentBaseView` to be inherited by any settings view that is not index.
- Updated Settings templates appropriately to work with new views
- Removed extraneous `active` class from `settings-content`
- Changed settings menu to use `gh-activating-list-item`
- Retooled settings tests

 ### Mobile Utils
- Renamed file to `mobile.js`, since it's inside of `utils/`
- Added `mobileQuery` MediaQueryList to help detect layout changes
- Removed unused `hasTouchScreen`, `device.js` should be used instead.
- Removed unused `smallScreen` function
- Moved FastClickInit to codemirror-mobile