Updated TODO

darcs-hash:20090226151736-58103-04672f4cb68f0ffea2e52e56403adb7361eaefcf
Add special PJSIP module to core to add headers to outgoing SIP message

- Add "User-Agent" header to every outgoing SIP request
- Add "Server" header to every outgoing SIP response

darcs-hash:20090226170325-58103-dd77eb425b51da87afff61a2ac5fa6437339b104