Refactored ICE transport interation

Ignore-this: 17201533c5a8573ec8a4ad3f2ad291b3

- Better state notifications
- Added ICECheck and ICECandidate datatypes
- Removed no longer needed attributes from RTPTransport
- Save SDP RTP information on the stream instead of the transport

darcs-hash:20130610102143-56b4d-308791a99a802f31d836c9eec86b675db22ed229
Adapted to changes in re-INVITE handling API

Ignore-this: ed333cad893c3804381092d7559d4c1c

darcs-hash:20130610102444-56b4d-13fded1d7eba064207cb26a9828c0f7474dbeaab
Don't parse each PJSIP log line, send them transparently to applications

Ignore-this: 65fea840c837d2320e5425ab729c6b8a

darcs-hash:20130415081557-56b4d-cc3f12ce08f2890f9d8222c04c38771dbe03bb92
Enable PJSIP log indenting for increased readability

Ignore-this: 9a88132c4ae6941534f9d1cacb847335

darcs-hash:20130415084632-56b4d-b49bb87cc63345155c23fc67f7f3d523ded1f962
Fixed setting Contact header when creating dialogs

Ignore-this: a8b61e1ec7d56bbe731295c18db9258

The PJSIP API changed, and it now needs a string conforming to RFC3261, sec 20.10,
that is, it needs to be enclosed in angle brackets or otherwise the parameters will
be added as header parameters instead of URI parameters

darcs-hash:20130419075329-56b4d-09bf9311c2fa6b17331c816c2953eda07f08a084