Comment 2 for bug 1793585

Testing changes for Ubuntu 18.04 and Evergreen indicates that many of the Perl warnings that we've been ignoring for years have come back to bite us. Both make check and make livecheck fail at least one test, the latter fails multiple. The failure of make check involves a warning that has become illegal in Perl 5.26. I suspect, but have not taken the time to investigate, that the live tests fail for similar reasons. I am calling it a day for now, but I will take this up again, later.