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

...roblems

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.

This makes ODP.NET the default underlying .NET provider for the Oracle provider. I think it is better to do that because (a) it works on ODP and does not completely work on Microsoft's System.Data.OracleClient because of problems in that, and (b) because System.Data.OracleClient is deprecated.
This does not yet include an update to the README.md file but I'm working on that. If you want to hold off on merging it until that is done, just tell me and I'll add it to this branch and push it. I figured it would be better in a separate pull request.