Added Better Unit Tests for Signatures Controller

I modified the App.Config and Web.Config files to allow for the unit
tests to run against a different database from the regular app. I added
code to the unit test project to automatically clear the database as
well as fill it up with random data.

The connection string in app.config is a hard-coded file system path.
This will be unacceptable for the release, and a better system should be
found in a future release.