Environment for pgsql test is added

The source of this approach: https://github.com/ds125v/moodle-travis/blob/master/.travis.yml
I've modified it slightly to simplify the 'sh' usage and new databases addition as a result.
The qcubed examples sql script for PostgreSql database

This script was originally created in the feature-Composer branch.
Fixed a copy-n-paste error
Using getenv instead of the $_ENV variable.

The $_ENV variable is empty on my local machine in cli and normal mode and on a travis-ci server too.
Merge pull request #142 from olegabr/feature-80

Feature 80