Added new channel command FTDM_COMMAND_SET_POLARITY
ftmod_wanpipe - Added support to enqueue polarity events on FXO lines
ftmod_wanpipe - Added support to set polarity on FXS lines
ftmod_analog - Added support to answer and hangup FXO lines on polarity reverse
ftmod_analog - Added support to reverse polarity in the FXS line on answer and hangup
mod_freetdm - Added parameters answer-on-polarity, hangup-on-polarity and polarity-delay
to enable those analog features
if this parameter is set to 0 ftmod_analog will not wait
for dial tone before dialing out the requested number.
Anything bigger than 0 is the units in milliseconds to
wait for dialtone before aborting the call.
