rsocket: Add sample application to copy files over rsockets

rsocket: Add sample application to copy files over rsockets

rcopy will copy files from a source system to a specified remote
server.  It's essentially a really dumb FTP type program that can
be used to quickly transfer files between systems, which can be
useful to verify data integrity.

(It was easier to create this program than modify an existing FTP
client and server application, which was my first choice.  Fork
support is difficult.)

Signed-off-by: Sean Hefty <sean.hefty@intel.com>