add conference_member_id variable to all sessions with the member id used by their conference participation (For drk__)

Resolve MODSKINNY-1:  FreeSwitch stops working when I use a cisco 7910
phone - FREESWITCH 1.0.6

This is hackish

Thanks to Peter Olsson

Closes: MODSKINNY-3

         fix fxs features

This solves incorrect display on the phone.

BUT: this creates a delta because the SQL value and the value known by
the phone. I hope this doesn't break other things.

(NB: the original problem here was the unability to do an UPDATE inside
a SELECT callback)

- send SWITCH_MESSAGE_INDICATE_DISPLAY when ringing (after knowing calle
  info
- send call info when receiving SWITCH_MESSAGE_INDICATE_DISPLAY

The send SWITCH_MESSAGE_INDICATE_DISPLAY part doesn't work yet, because
partner channel is locked (have to find out why)

- wait for media before marking channel as answered
- set effective_caller_{id,name} before sending call info