Refactore slug API for generating tag and post slugs.

Closes #2601
- Removed slug generation from the post API
- Added new, self-contained slug API
- Fixed slug permissions in the fixtures files
- Added a HTTP route for the new API method
- Added integrational tests
Fix up url helper unit tests

Closes #2817
-use async semantics for tests
-fix api.settings.read stub for the url helper describe block
-rename test to describe actual behavior (return '/' instead of '')
Fix 403 errors after signup

Closes #2819

- Keep around the _csrfSecret on the session after regenerating
Merge pull request #2818 from jaswilli/issue-2817

Fix up url helper unit tests
Merge pull request #2814 from lennerd/issue-2601

Refactore slug API for generating tag and post slugs
Clean up routes. Use new slug endpoint in admin.

refs #2814
-removed route /posts/slug/:title due to API change
-changed admin to use new slug endpoint
-removed duplicate notifications routes
Update Ember Components with proper gh- prefix

GH-ISSUE 2373
Ember Data with Posts

Ref #2699

- Introduce ember data dependency
- Add loadInitializers and refactor most initializers into one combined
- Add Post ember data model
- Refactor generateSlug to use title of post and ghostPaths
- Refactor post controller to not reference model.property everywhere
- Use RESTAdapter for posts, users and tags
- Setup author and tag relations in Post model
- Fix broken API calls by adding CSRF header
- Add initiaizer for csrf value
- Use actual User model for current user initializer
- Add action for setting featured post, test with actual api call
- Fix the sending of UUID's up to the server
- Refactor current-user to use ember-data store
- If a user is preloaded in the application, use pushPayload to put it
in the store
- Do a lookup on the store to get an actual User model for injection
- Fix posts/post controllerName in route/new.js
- Alter signup process to push user into ember data store
Merge pull request #2826 from jaswilli/route-cleanup

Clean up routes. Use new slug endpoint in admin.
Merge pull request #2718 from jgable/emberData

Ember Data with Posts
Merge pull request #2828 from lholmquist/GH-2373

Update Ember Components with proper gh- prefix
Merge pull request #2820 from jgable/fix403

Fix 403 errors after signup
Use new slug endpoint in ember admin

Closes #2831
-use new slug endpoint in fixture
-use new slug endpoint in post model
-do not try to generate slug for zero length titles
Fix up unit tests. Check config url with isURL.

No issue
-validate url in config.js using validator.isURL
-fix up async flow in bootstrap unit tests
-make sure done handler is called on async tests
Merge pull request #2832 from jaswilli/issue-2831

Use new slug endpoint in ember admin
updated express-hbs to 0.7.10
Updated grunt-update-submodules to 0.4.0

closes #2503
 - It can now have custom additional parameters to `git submodule update` instead of always having `--init --recursive --merge`
Infinite Scroll on Posts List

closes #2414
- Add PostsController with loadNextPage action
- Collect and store pagination info from PostsRoute into PostsController
- Use `store.filter` on PostsRoute model hook to auto-update posts list template as post models are added to the store
- Add content list view and use it to check for scroll event
- Make PostRoute only load a post that's already in the store, until we figure how to load multiple pages on refresh
- Add util function from clientold that concats error messages from server response
Merge pull request #2838 from aiampogi/master

Updated grunt-update-submodules to 0.4.0
Merge pull request #2837 from iBotPeaches/updated_express

updated express-hbs to 0.7.10