oai-pmh add extra type information

Motivation:

OAI-PMH provides information about resources.  The PaNOSC OAI-PMH
endpoints are not limited to describing datasets; therefore, it's useful
to show which of the items are of which type.

Modification:

Update the main repository cell to include type information.  If the
repository is using sets then the sets table now includes type
information.

Result:

A better understanding of which resources are available.