skip looking up session again in hash table when we already are parsing the event from the session thread

update show calls to show both 1 legged calls and bridged calls, also show bridged_calls for previous behaviour of show calls

sdp_m_per_ptime is now implied to be true, if you don't like this set it to false but its going to be undefined behaviour.  This basically means if you call in with ptime 30 then you have a bunch of ptime 20 codecs in your outbound list that there will be one m= line with 30 and the original inbound codec and more m= lines for each discinct ptime in your list.  This is, of course, will depend on disable_trancoding or absolute_codec_string as well