Correcting push jobs documentation

While setting up a trial of the Push Jobs Server I found there was missing information in the docs with respect to ports, etc. Feel free to clean up the formatting here but this is what I found.

The ports info should probably get pulled out into another doc (if there is one, I couldn't find it) since all the pedant tests wouldn't run without these ports being opened through the firewall. (Pedant will hit all the ports through the api_fqdn of the box.)