When analyzing environment variable changes applied by shell script
passed as argument, produce a `setenv` modulefile statement for any
variable found set prior script evaluation and for which value is
completely changed after script evaluation.
Fixes#320
Inhibit output generated by scripts evaluated by createmodule.sh and
createmodule.py to ensure these outputs will not get in the way when
analyzing the environment change done by the evaluated scripts.
Fixes#309
Fix createmodule.sh script to correctly analyses environment when shell
functions are found defined in it. These shell function definitions are
skipped.