Move username, isEnabled, confirmationToken, and timePasswordRequested from custom fields to User class properties.
Merge from master.
Don't throw an exception when attempting to store an empty timestamp. Coerce it to null instead.
Add support for migrating the database from version 1.x to 2.0 and back again.
Update migration instructions.
Update migration docs.
Update migration docs.
Update test class name.
Add a note about upgrading to the README.
Update README formatting.
Update README.
Update copy.
Throw an exception if database schema is out of date.
Update MIGRATION.md
Update MIGRATION.md
Update MIGRATION.md
Update MIGRATION.md
Fix bug causing email address to be stored as username.
Merge branch 'master' into 2.0