LibAAH_RTP: Add unicast mode support to the RXPlayer

Add support for unicast mode to the AAH RXPlayer.  At the API level,
things should be pretty simple.  To use unicast mode, instead of
passing the multicast address and port in the data source URL, just
pass the unicast address and port of the transmitters command and
control port.  For example, instead of

aahRX://224.128.60.5:8867

one might instead pass

aahRX://192.168.63.5:55476

Change-Id: I7b40716983d7a91def86dcf40f093dda4255aae3
Signed-off-by: John Grossman <johngro@google.com>