Allow osTicket to install on a database cluster

The problem stems from assumed MySQL insert ids. In MySQL clusters, the id
numbers will not necessarily be consecutive. This patch causes the install
and upgrade patches to lookup the assumed values for the linked id numbers.
Use database default storage engine

Drop required usage of MyISAM tables, and drop fulltext indexes as they
are not used in the code currently anyway. Also, use a blob to store
session data so as not to waste space with UTF-8 encoding. Lastly, fix
session_id storage to use VARCHAR(255) which is required for versions
of MySQL < 5.0.3, and use ascii for the storage model for the
session_id as it will contain simple characters only.
Migrate to new session storage model
Use ticket default department=0

Since the first department id cannot be assumed
Merge pull request #568 from greezybacon/feature/cluster-db

Allow osTicket to install on a database cluster

Reviewed-By: Jared Hancock <jared@osticket.com>