speed up "apt update"

add /etc/apt/apt.conf.d/30usability-misc

Acquire::Languages none;
Acquire::IndexTargets::deb::Contents-deb::DefaultEnabled false;

It's roughly 140 KB vs 43 MB. Seconds vs real delay.

I wonder if this should become the default for Whonix and Kicksecure.

We'd loose translations something. I don't even know where - since I always use English as default language - to be on par with the defaults that users will use. Probably translations for `apt-cache show pkg-name` or so. But only for those who change the system language for APT. Dunno if anyone is doing that actually. If that's a problem, it would be better to have instructions how to reactivate this for desired languages only.

We might also loose default `apt-file list pkg-name` but those who want that can (and probably have to use anyhow) `sudo apt-file update`.

https://forums.whonix.org/t/speeding-up-apt-update-with-acquire-languages-none-and-contents-deb-defaultenabled-false-its-so-much-faster/8894

etc/apt/apt.conf.d/30usability-misc

@@ -0,0 +1,6 @@
+## Copyright (C) 2020 - 2020 ENCRYPTED SUPPORT LP <adrelanos@riseup.net>
+## See the file COPYING for copying conditions.
+
+## https://forums.whonix.org/t/speeding-up-apt-update-with-acquire-languages-none-and-contents-deb-defaultenabled-false-its-so-much-faster/8894/2
+Acquire::Languages none;
+Acquire::IndexTargets::deb::Contents-deb::DefaultEnabled false;