* add CRON_SAFE_MODE to example config file, fix some bugs, add an unrelated low-priority TODO
* create CRON_SAFE_MODE to disable parts of cron for use after extended outage - fixes https://github.com/HabitRPG/habitrpg/issues/7161
* fix a bug with CRON_SAFE_MODE, remove duplicated code, remove completed TODO comment
* fix check for CRON_SAFE_MODE