Wrongly logging ordinary comments as parsing ERRORs
When parsing my system crontabs, 2 ordinary comments are assumed to be invalid, disabled jobs and an `ERROR` is logged:
- from `/etc/cron.d/mdadm`: `# Copyright © martin f. krafft <madduck@madduck.net>`
- from `/etc/cron.d/sysstat`: `# Activity reports every 10 minutes everyday`
```pycon
>>> from crontabs import CronTabs
>>> c = CronTabs()
Missing user or command in system cron line.
Missing user or command in system cron line.
```
Given that comment parsing for disabled jobs can never be 100% accurate, why not silently ignore such lines, or at most log them as DEBUG instead of error? In the end they are assumed to be _invalid_ "jobs" anyway, and hopefully consider them just ordinary comments in a cron file (as they **are**)
python-crontab v2.6.0 installed from pip
issue