Meet "unary operator expected" error when use psql in rhcsh but
postgresql is not added to app

https://bugzilla.redhat.com/show_bug.cgi?id=1088159

Try to connect to the postgresql without the cartridge added to app,
will meet the error "bash: [: =: unary operator expected".
Merge pull request #5299 from bparees/psql_unary

Merged by openshift-bot
Adding test coverage