Merge changes Ibd11c0a8,I11fe6201,I63049dbb,I97ef3f26,I11cbffde, ...

* changes:
  rusty-gd: clean up imports & pub exports
  rusty-gd: remove one level of indirection for hci facade proto
  rusty-gd: collapse facade implementation into facade.rs
  rusty-gd: move hci facade client contents to root server
  Start integration with gd rust & cert tests
  GD: signal on signal port when server is ready
  Catch sigint to shut down BT testing process