1) Added additional edge case for installer that I missed.
2) Reference class via use statement and correct namespacing.
3) If we are using the docker environment set certain defaults from environment variables instead of hardcoding.
1. Bumped the PHP version in the PHP Docker file so that composer can run successfully as some packages are depdendent on PHP 7.0.8 or higher
2. Added a composer image that is dependent on the same version of the PHP container so that there are no issues running composer.
Jeremy Quinton
Tristan Guo
Yoann Lecuyer