Acq: you can now back up to old search results

Acq: you can now back up to old search results

This works by changing what actually happens when you click "Search."
Instead of running your search instantly, the search interface turns your
search into URL parameters and redirects you.  This way you get a new entry
in your browser history (much as if you were doing a non-AJAX search).

When the search interface is run with these URL paramters, it actually runs
the search and shows you the results.  This has the added benefit of
allowing other interfaces to link to prepopulated searches, and potentially
giving users a way to save searches in the future.

Incidentally also added "new invoice" menu item.

git-svn-id: svn://svn.open-ils.org/ILS/trunk@16178 dcc99617-32d9-48b4-a31d-7c20da2025e4