Huge changes to Oracle provider to support ODP.NET and fix a number of problems

Also add in a missing parameters reset when reading referenced tables.

This Oracle provider works on ODP.NET and mostly on Microsoft's built-in
System.Data.OracleClient. It should be easy to make it work on any other Oracle
provider for .NET.
Merge pull request #366 from BruceCowan-AI/RealOracleClient

Huge changes to Oracle provider to support ODP.NET and fix a number of p...