Added "log_level" init and runtime option for PJSIPUA, sets PJSIP log level

darcs-hash:20081217152148-58103-05fe319ce0c19495b64f9922e20d801ee70361a6
Updated TODO

darcs-hash:20081217153400-58103-d1182b939984e3eb32291d8b5f26c942b7fe4cef