[Koha] upgrade script

[Tonnesen Steve]

I managed to put together an upgrade script today that will be going out
with the 1.2.1 release.

The upgrade script (koha.upgrade) will make backups of your koha data, and
all of the koha scripts and html files before installing the new files and
making any necessary changes to the database.

The upgrade script also indicates changes that may need to be made to the
Apache configuration.

I suspect there aren't a whole pile of production Koha systems out there
yet, apart from Katipo's clients and my schools.  If you _are_ using Koha
in a production environment, I'd really appreciate hearing from you before
the 1.2.1 release goes out.

Steve.