Fixes bug where module list output went to stderr
Fixes bug where module list output went to stderr

(also changes exit code for not being able to load a module from 3 to 4)

UCL-RITS/rcps-buildscripts,UCL-RITS/rcps-buildscripts,UCL-RITS/rcps-buildscripts,UCL-RITS/rcps-buildscripts,UCL-RITS/rcps-buildscripts