Fixed printing of RTP parameters changes in sip_audio_session script

Ignore-this: 5887fad7356bbc4db473c0e6e29cbb57

darcs-hash:20100104113709-1e3d8-35a911d2e280d5eb3939afd0a1e5eefa91def1f9
Fixed Invitation to only update the To header from the first 200 OK

Ignore-this: 26d22072cbea46b411699823ecf4e81b

darcs-hash:20100104120101-1e3d8-8ab84a719d6c91591ccea47913d7f6d4f42d5836