Add failing capitalization tests for address_info
address_info is now case-insensitive with both json and mysql databases
address_info now returns the email's canonical form
Update the front end for email canonicalization.

The theory:
* Get the canonical form of an email as soon as the user types it in.
* Pass the canonical form around so there is no worry as to what email is being worked with.
Check to make sure sign in is case insensitive in dialog and on main site
Merge pull request #3078 from 6a68/case_sensitivity

Case sensitivity phase 1