input and output files now live in user-specific directory. output line is written twice: to item key-value store (.nanni) and to sequential log (.nanni.log). unless 'new' is specified in querystring, show the current annotation from the user (not yet supported for preposition tags).
input in data directory rather than user directory; preliminary version browsing support
- &u=userID to log in as another user, subject to constraints based on
  the authenticated user; this is shown in titlebar
- previous/next navigation buttons (which do not save); can be turned off
  with &nonav
- &readonly mode
- version history iframe(s) activated with &v, &v=+, &v=+userID,
  &v[]=+user1&v[]=user2, or similar. can be filtered by user; + expands
  the version iframe on page load; &nooutdated hides all but the latest
  version from each user. &nosubmit&noinstr&readonly&embedded is specified
  for the embedded page.
- continuing to the next page on submit now processes $_GET and $_POST
  directly so querystring options won't be lost