Add telecomm registration support to SIP.
Changes in CL:
1. Add SipAccountRegistry to manage telecom registrations
2. Register all accounts on ACTION_SIP_SERVICE_UP
3. Register specific account on ACTION_SIP_ADD_PHONE
4. Unregister specific account on ACTION_SIP_REMOVE_PHONE
5. Set the unique SIP uri as the PhoneAccount ID
6. Read phone account handle for outgoing calls instead of showing
a proprietary SIP chooser dialog, which I removed (see
7. Moved some of the error condition codes and error dialogs from
SipProfileChooser to SipConnectionService.
8. Set Phone account handle as extra on the incoming-call intent
9. Remove build files for SIP directory since it is already built into
18 files changed