Update c3p0 to 0.9.5-pre8 to get support for unwrap.

We want this to use in the secondary, but both versions from the data-coordinator
and the secondary end up being loaded into the classpath.  :(
Also update to newer postgres driver for wrapped connection support.
Merge pull request #6 from socrata/marcs/update-c3p0

Update c3p0 to 0.9.5-pre8 to get support for unwrap.