Previously setup_capture_of_logs would prevent log messages from
going to the console entirely.  That's a problem, since sometimes
log messages are bugs!  Now setup_capture_of_logs() acts sensibly.

If you really do need to keep a message from going to the console
entirely, there is setup_full_capture_of_logs().  But only use that
if you're prepared to make sure that there are no extraneous
messages generated at all.