Migrates email user options to a new data structure, where `email_always`, `email_direct` and `email_private_messages` are replace by
* `email_messages_level`, with options: `always`, `only_when_away` and `never` (defaults to `always`)
* `email_level`, with options: `always`, `only_when_away` and `never` (defaults to `only_when_away`)
Changes to functionality
- Removed syncing of user metadata including gender, location etc.
These are no longer available to standard Facebook applications.
- Removed the remote 'revoke' functionality. No other providers have
it, and it does not appear to be standard practice in other apps.
- The 'facebook_no_email' event is no longer logged. The system can
cope fine with a missing email address.
Data is migrated to the new user_associated_accounts table.
facebook_user_infos can be dropped once we are confident the data has
been migrated successfully.
When the setting 'full name required' is on the anonymizer was trying to set the user name to nil and this caused the user name and email to remain not anonymized.
Now in this scenario the user name is set to the anonimized username and the email is anonymized correctly.
As it stands we load up user records quite frequently on the topic pages,
this in turn pulls all the columns for the users being selected, just to
discard them after they are loaded
New structure keeps all options in a discrete table, this is better organised
and allows us to easily add more column without worrying about bloating the
user table
