rx_fm: rtl_udp, fork of rtl_fm with UDP controls

[rxseger]

Investigate/integrate rtl_udp into rx_fm, or similar functionality, could be useful to allow retuning without restarting the program:

His fork allows retuning of the rtl_fm program via UDP without the need to restart the program. In the future he hopes to support UDP PCM streaming

http://www.rtl-sdr.com/rtl_udp-port-rtl_fm-udp-controls/

https://github.com/sysrun/rtl-sdr/blob/master/src/rtl_udp.c