Improve reset password views

Added reset password mobile views[ci skip]

Cross-Origin Resource Sharing

Remove partial support for CORS on webfinger routes and replace
it with the Rack::Cors middleware. This provides more complete
CORS support and works around a caching issue with nginx on
Heroku and potentially other reverse proxies.

CORS headers are only added if the incoming request includes
an "Origin" header, which seems to be correct according to
the CORS spec.

closes #2216

This reverts commit 061badf7.

oembed video thumb [oh yeah]

Legacy browser support

Added localized text in comment view

Improve mobile sign up and sign in view [ci skip]

Added localized text in getting started view [ci skip]

totally gross js load order problem.. make the widget system fire after the backbone app to get the notification and search autocomplete back

fix for #2770

Fix #2974, markdown headers now different from headers in post [ci skip]

made the "loader" gif background for oembed container
make videos autoplay after click

disable superscripts on server-side markdownify, since they are disabled...[ci skip]

#2823 fix unlike and unfollow update 

Fix to allow white spaces in Rails.root path for the integration rake task [ci skip]