Changed default html slightly.

Changed change button to edit button.

other pages.

to...".  Changed the contents list to be a table.  Removed various
whitespace.

compatibility.  Added PrincipiaTime which returns a DateTime object.

in index, but get them on demand from doc.

Removed vestiges of InvertedIndex.

find 'Application' it would (on bsdi, anyway) raise AttributeError and
only KeyError was being caught...

non-threaded environments.

Took stab at expression documentation.