[UID] Basic fixes on setting the UID.

* Got the setuid() function to work by moving it out the (I think) jQuery
  specific elements and into a 'top-level' definition.

* Only call the function, after the body loads, to make sure sure the
  DOM elements can be found.

* Currently sets the value of both the #id and #fingerprint elements.
  It might be the case that only one of those needs to be set, but not
  sure yet.