Add a uttility in Teiid Client plugin to construct a VDB Manifest (xml)

In order to import full deployed VDBs on the server we'll need a mechanism to get Data Roles/Policies, Translator Overrides, etc. that are defined in a deployed VDB manifest. Unfortunately, Designer's ITeiidVdb is designed to be simple and the info is only available via Teiid's VDB interface, which isn't part of the Admin API.

Suggest creating a utility in the teiid.client plugin that can take a VDB and construct the basic Manifest, or -vdb.xml string down to the <model/> elements.

Then, by adding a getManifest() method to our ITeiidVdb interface, Designer can create a full DDL-based version of a deployed VDB using that method + the Teiid Server's getSchema() method.