Implement enough device discovery to grab the host/ip/port for debug.

This works by putting up an activity to grab that result string
for debugging purposes. It needs to become a DeviceInfo but a String
gets the job done for tonight.

A DeviceDiscoveryManager wraps up Android's NsdManager so that our
 Adapter doesn't have to know squat about NsdManager. It just gets
 fed from the manager and updates our ListFragment.

 Special thanks to my friend Jonathan <github=iNoles> for helping me
 understand the Fragment lifecycle and debugging.