[horde] oci8 session handler for horde SessionHandler framework

[Liam Hoekenga]

Hey guys -

Here's what I've got..

    http://www.umich.edu/~liamr/horde/SessionHandler_oci8.php

It works against the release of Horde 2.2.1.

I used the sql, mysql and pgsql drivers as skeletons - both logically and
syntactically (thanks to Jon and Mike).  It's working on our test box, but that
doesn't have much a load.

Rename it oci8.php, drop it into lib/SessionHandler, and use "oci8" in the
appropriate parts of config/horde.conf

Liam