Get PG tests running standalone on MNMG cluster

[rlratzel]

The nightly MNMG test/benchmark runs include PG tests, but are not easily run by developers outside of the automated environment.

This task is to get a developer set up to run the PG tests on a MNMG cluster, which involves getting access, understanding the job scheduling software, and several other aspects, all of which can be time consuming. Doing this first allows us to focus on development of larger-scale MNMG PG support easier.