Mapping extensions to languages is broken #1483
Description
In PR #1464, I discovered that cmsAddSubmission without --lang defaults to the first language on the list which matches the filename extension, regardless of what is enabled in the contest. The test suite did not originally catch this, because it used C which has only one version enabled.
All callers of cms.grading.languagemanager.filename_to_language seem to be affected, in particular cmsMake and cmstestsuite/web/CWSRequests.py.
cmsAddSubmission is already fixed by PR #1464, but the other places need attention, too.
@veluca93 mentioned that cmsMake can be probably removed.