Allow the use of pushdown functions without requiring Java programming

Currently, in order to use a database function, even if pushdown is required, it is still necessary to add the function interface to a Java class within the connector, and the connector then must be deployed to the server in order to allow for this pushdown function to be used within the Designer. This creates a lot of extra effort every time you want to make use of a new database function. Particularly, given the schema designer doesn't necessarily have access to either the connector code or the server, and then must involve other parties simply to be able to use an additional database function. It would be very beneficial to speedy schema development if that was not necessary, and if, say, the interface could be defined on the Designer side, added to the VDB, and then deployed as part of the VDB.