Eliminate progress reporting which is useless in logs

[YSakhno]

Hello,

I've made this little change that sanitizes logs a little by filtering out information about progress during software/packages install. Without it logs are full of (Reading database ... 5%^M(Reading database ... 10%^M and so on stuff.

Yuri Sakhno.

[coveralls]

Coverage increased (+0.2%) to 57.597% when pulling 87dd127 on YSakhno:no-progress-in-logs into b0177f0 on xen-tools:master.

[coveralls]

Coverage increased (+0.08%) to 57.482% when pulling 230167d on YSakhno:no-progress-in-logs into b0177f0 on xen-tools:master.

[xtaran]

Hrm, while I do see that progress reporting doesn't make sense in log files I strongly dislike the idea of having "quiet" logs. First need to check how quiet --quiet is.

[YSakhno]

Actually, I cannot see the difference with and without --quiet (did not check very thoroughly though).

And --quiet (of any level) is not enough to silence the 'Reading database' messages because those do not come from apt-get according to this: https://bugs.launchpad.net/ubuntu/+source/apt/+bug/874409

[xtaran]

I just went through dpkg's options and found none to silence it. The only one which might help here is --status-fd.

[YSakhno]

Well, yes. That's why the need for sed-filtering. If you are not comfortable with --quiet option, you may omit it, I am fine with that (since it seems to make no real difference whatsoever). Just be sure to keep sed-filtering in place.