- improved adress bar for file-browser:
 * better use of some polymer features (getting the model in a repeat template's on-click event)
 * "pseudo" navigation up a path works
- file-browser now pretty much working:
 * moved new implementation to file-browser2.html
 * adress/navigation bar works
 * going deeper into file tree by clicking on folders works as well
 * correct events are generated when selecting a file or folder
 * overall clean up
 * note : for display, current version now depends on icons from https://github.com/zcbenz/nw-sample-apps/tree/master/file-explorer (not included in this commit)
- small amount of cleanup and experimentation with servo-controls
 * min & max values are now using number inputs
- updated accell-compass:
 * cleaned up code
 * better use of websocket/socket.io for the relevant version of the component
- improved web-socket and socket-io components
 * correct handling of startup and cleaning at "shutdown"
 * handle failure to import socket.io gracefully
 * overall cleanup
- remove a few useless console.log messages from file-browser2