Initial impl of stored procedure based binding creds

[cf-gitbot]

We have created an issue in Pivotal Tracker to manage this:

https://www.pivotaltracker.com/story/show/180344013

The labels on this github issue will be updated when the story is started.

[asalan316]

Improvement suggestions are good. but as a first step, we want to check whether it is working (cut a release).