Added max_reconnect_delay (10 minutes). No sense backing off indefinitely.
$self->_users_by_id replaced by $self->state->twitter_users
Makes more sense to test twitter IDs rather than screen names. So, store the authenticated user and we'll have both.
Although, only friends can send direct messages, so senders should already be on board.
This is certainly true for the embedded status returned by verify_credentials.