TODO ITEMS:
- add a grid column picker
- commit changes
- add relations (entry/feed), e.g.

	// category: new table with one item (type=entry)
    <link rel="http://schemas.microsoft.com/ado/2007/08/dataservices/related/Category" type="application/atom+xml;type=entry" title="Category" href="Products(2)/Category" />

	// order details: new table with several items (type=feed)
    <link rel="http://schemas.microsoft.com/ado/2007/08/dataservices/related/Order_Details" type="application/atom+xml;type=feed" title="Order_Details" href="Products(2)/Order_Details" />

	// navigate back to the parent table
