- jumpToElement now works when given an id string in the form of "0" +
  docId
- the address of the labels is now done using id strings to make sure that
  when the objects are moved that the labels point to the correct address.
- copy branch now generates unique ids for all of the objects in the
  branch when copying.
- added code to remove duplicate ids from existing documents
fixed bug with selecting the root node in the center window