added filter to twilio_message transition

and changed timestamp to use toISOString().
fixed bug in registation transition

call setId with the right params.
added configs check to filter for registration transition

Added config check to filter, it makes the transition queue a little
more efficient, hopefully speed things up.
fixed a few bugs in accept_patient_reports transition #49

Removed repeatable:true, since the transition would create an infinite
loop and good way to prevent that I could think of.  Not sure why it was
repeatable in the first place since it only makes a few one-time changes
to itself (adds messages repsponses) and to registrations (clears a
schedule group).

Also added hasConfig() on filter to only call onMatch when necessary.

Fixed bug where the "to clear" list was spilling over into the next
group, instead of remaining within the group. We only want to clear one
group at a time via SMS patient report.

Fixed bug where messages other than 'scheduled' state were getting set
to 'cleared'.  We only want to clear scheduled messages. Sent, pending
and muted should remain unchanged.