More work on the Odata data source.

It's coming along.  It now functions properly within the structure of
the query lifecycle, handling queries in their proper order.

I've also gotten its interrogation of the service for the field names
working, including a pretty trick bit that matches up the "entity set"
name with the entity type name.

Next on the to-do list is to implement composing of OData filter
strings.  This is analogous to SQL where clauses, and thankfully has a
similar (if somewhat less robust and readable) syntax.  That happens in
the misc.js file that got altered in this commit.  The new function in
there is the entry point into that process.