Keep deep linking through user login

[stianjensen]

When you click the edit button, but are redirected to the login screen, we keep the link to the edit screen in the URL. This ensures that the user is sent to the edit screen after login in complete.

However we sometimes pass the line number you want to edit from as part of the edit url in the hash fragment section (or whatever it's called).
This information is lost when going via the login screen.