ULib - This patch adds PostGres test alongside with minor fix

This patch adds PostGres test database alongside with minor fix...

All tests are passing as per [my Travis-CI build log](https://travis-ci.org/stefanocasazza/FrameworkBenchmarks/builds/45049685)
Please see the [prerequisites.sh](https://github.com/TechEmpower/FrameworkBenchmarks/blob/master/toolset/setup/linux/prerequisites.sh#L32) file. It already adds most of these, feel free to add the new dev libraries ulib requires, and remove this line from your own `install.sh`. Thanks!