add accessor for human readable UID to Device
removed unused instance variables from Device
renamed UIDString and uid to have more clear names in public interface of Device
stricter encapsulation between Device and IPConnection (using a method that is not publicly visible)
introduced dedicated (struct) type for UID
simplified internal AddDevice (exposes fewer details of its implementation)
public interface of Device now only provides a UID-string, internally UID stays an own type
Merge remote-tracking branch 'upstream/master' into csharp_uid_accessor
Merge branch 'csharp_uid_accessor' of git://github.com/NobodysNightmare/generators