CHANGES:
prevent multiple CONNECT messages after +FRH=3
initialize tioflags before using (Robert Boisvert, Alpine Linux team)
partially import a change from upstream libiax2 to address invalid read
size in iax_get_event (Robert Boisvert, Alpine Linux team)
import a change from upstream spandsp to address uninitialixed value
in at_cmd_plus_VSID (Robert Boisvert, Alpine Linux team)
The source code for IAXmodem can be downloaded here: http://sourceforge.net/project/showfiles.php?group_id=148814.