Corrected link to user profile settings

closes #2745
- Added link
Validate user URL input to ensure protocol is present

closes #1623
- added protocol validation to isURL on user settings validator.
- added placeholder URL to user profile template
- ref: https://github.com/sethlilly/Vapor/issues/10
- ref: https://github.com/oswaldoacauan/ghostium/issues/38
Improve signin

Ref #2413

- Remove fixture and use actual API
- Store and send down actual logged in user data
- Refactor isLoggedIn to use computed property on application
- After signin, update user data in dependency container
- Add CSRF to all routes and controllers via initializer
- Update authenticated route to check for user.isLoggedIn
- Add notifications for signin error
- Add notifications.showAPIError helper
- Add plumbing for refreshless signup to doSignUp in admin controller
Correct behaviour for trailing slashes

fixes #2741
- Extend HistoryLocation
- Add trailing slash to path
Add /content redirect to Ember admin.

Closes #2746
- Adds content route to router
- Content route transitions to posts route in the beforeModel hook.
Merge pull request #2734 from shindakun/userurl

Validate user URL input to ensure protocol is present
Merge pull request #2772 from shindakun/profilelink

Corrected link to user profile settings
Merge pull request #2765 from novaugust/ember-content-redirect

Add /content redirect to Ember admin.
Merge pull request #2771 from halfdan/2741-trailing-slashes

Correct behaviour for trailing slashes
Merge pull request #2764 from jgable/emberSignin

Improve signin