initial stub of data server client code in Interface
stubbing of mechanism to confirm packets sent to data server
add UUID helper class to get UUID string without braces
pack string representation of UUID for data server communication
link mesh URL and UUID in prefs to data server client
store username and not UUID for MyAvatar
set username instead of UUID in Interface preferences
ask for a mesh if username is present on login or is changed
shore up receipt of face mesh URL from data-server
clear the face model URL if the username is changed in preferences
Progress towards a spring-mass model.
add method to DataServerClient to resend unmatched packets
Got some actual damped oscillation going.
Merge branch 'master' of https://github.com/worklist/hifi into springy
Fix for eyes rolling back in head.
Fix for macaw head without mapping file.
Merge branch 'master' of github.com:worklist/hifi into nameserver
Merge branch 'master' of https://github.com/worklist/hifi into springy

Conflicts:
	interface/src/renderer/FBXReader.cpp
Merge branch 'master' of https://github.com/worklist/hifi into springy
More springy, more damp.  Removed unused variable.