configconvert: fix already replaced quotes escaping

refs #2743
Compat: split cr output into (long_)output, log only output

status.dat requires output, and long_output seperated for proper
representation by guis and addons (they cannot be changed for
compatibility reasons, we must change).

logging an ALERT requires only the output (first line of the check
result output).

fixes #3882
fixes #4348
Merge remote-tracking branch 'icinga2/master'