Added post report feature

You can report a single post by clicking the correct icon in the controler section

Workflow:
* Report a post as offensive
* Trigger alerts to every pod-admin
* Pod-admin can review it in the admin interface
* Delete the post or mark it as reviewed
Absolute path added for favicon.ico
Remove alpha references to invites and buggy software
replace vendored backbone.js/underscore.js with 'backbone-on-rails' gem
- updates underscore to 1.5.2 and backbone to 1.1.0

backbone had some breaking changes:
- fix url/urlRoot handling in models & collections
- options are no longer attached to the view by default
- collections reset when 'fetch' is called, tell it to keep the existing
  models

other changes:
- fix some events triggering multiple times in connection with deleting
  a model
- use document fragments instead of an element array for stream entries
- adapt jasmine and cucumber specs to the changed code
  * no longer test the backbone router as part of our code
  * jasmine factory already returns model instances, no need to wrap
    that again
Merge pull request #4698 from goobertron/remove_alpha_refs

Remove alpha refs from devise.en.yml
Merge pull request #4662 from Raven24/update_underscore-backbone

update backbone.js and underscore.js
add permalinks for comments
Merge pull request #4700 from qmaruf/absolute-path-for-favicon-ico

Absolute path added for favicon.ico
bump recommended rubygems version
Merge branch 'develop' of github.com:diaspora/diaspora into develop
Updated image branding and files with refs to them
Submitted new images with blurred edges
new version of white2x
updated 158 locale files [ci skip]
Add gems upgrade in the changelog
Merge pull request #4709 from Flaburgan/update-changelog-gems

Add gems upgrade in the changelog
bump to 0.3.0.0
Merge branch 'release/0.3.0.0'
Merge branch 'release/0.3.0.0' into develop
start new development cycle