[rt-users] Need "DB_PORT" in Makefile and support throughout build

[Jeff Blaine]

>> We have our PostgreSQL database running on a non-default port.
> 
> This might seem a silly question, but why?
> 
> Alan Charlton

Not so much silly as irrelevant and somewhat indicative of the thought
that having a database server on a non-default port is "Wrong."

If it were wrong, there wouldn't be an option to run the database
server on another port.

It's on another port because we're running an older version of PostgreSQL
on the default port.

Defualt port:      7.0.2, been working fine for our other existing
                   databases, don't TOUCH IT.

Non-default port:  7.1.2, requirement of installing RT 2.x, in testing.