[Koha] cron issue with Koha on Ubuntu

[Mark Alexander]

Excerpts from Steve Nickerson's message of 2017-02-20 23:28:51 -0500:
> Thank you Mark!   As it turns out apparently my issue was that 'cron' was installed but not 'anacron'.   I had those same /etc/cron.d, /etc/cron.daily, etc. files that you provided, but anacron wasn't installed/running, so they weren't being used.   As soon as I added anacron things seem to be working now.  Maybe anacron should be one of the dependencies for the koha-common package???

I'm not sure I understand why anacron was required.  On both of the
installations I'm using, anacron was either not installed (Debian 8 on
Linode) or I had to disable it (Debian 8 in a VM on my laptop).
Anacron caused problems for me (and others) with Zebra being killed
off every morning.

See these discussions:

https://bugs.koha-community.org/bugzilla3/show_bug.cgi?id=16885
https://lists.katipo.co.nz/pipermail/koha/2016-September/046167.html