Added logging of DNSLookupTrace notifications to sipsimple.clients.log

Ignore-this: 20d7dab752fcdf13697ab85fd545c7b2

darcs-hash:20090626150000-1e3d8-00ce63ee8e10b43b2d093d127c59dcc4017a2493
Modified text in SIP trace logging

Ignore-this: e57199c90be2ae43a1e54dbdcaaad774

darcs-hash:20090626182430-1e3d8-099d58d896691446b265998f06f1b5466c016af1