Introduce the non-regression quick test mode. When the `QUICKTEST`
environment variable is set to 1, only the main tests from the
non-regression testsuite are run.
When first argument of the `mt` script is `quick`, tests are run in
quick mode.
Goal is to complete the quick tests in a minute, rather the 10+ minutes
required by the full testsuite.
Change license of mb, mlprof, modulecmd, mpub, mrel, mt, mtreview,
nglfar2ccov and playdemo scripts from GPLv3+ to GPLv2+.
Align this way all files from the Modules project under the GPLv2+
license.
Consent has been obtained from copyright holder to perform such move (I
hold the full copyright for these script files).
Related to #389
Add the save_test_env and reset_test_env procedure to record original
test environment (global and environment variables) and restore it once
a test set has been done.
Remove the --base64-failed-log option from the mt script as there is no
more need to output full test output serialized since the CI systems now
used can upload the test log files as artifact.
Abort download of icdiff, nagelfar or tclsh83 after 2 timeouts of 5
seconds and record download failure for icdiff to avoid mt script to
attempt a new download tentative every time it is called.
