i18n: add some statistics to commit messages
Update translations from Transifex

  24961 translated messages

Many thanks to:
 - es: Adolfo Jayme Barrientos <fitoschido@ubuntu.com>
 - fi: Larso <larso@gmx.com>
 - hi: libregeekingkid <rajuvindane@gmail.com>
 - nl: Simon Philips <simon.philips@gmail.com>
 - pa: A S Alam <apreet.alam@gmail.com>
 - tr: volkangezer <volkangezer@gmail.com>
 - uk: Yuri Chornoivan <yurchor@ukr.net>
 - zh_CN: leonfeng <chaofeng111@gmail.com>
update quassel.pot
Silence one more warning in miniz.c

Building on 32 bit machines causes some warnings related to undefined
macros; -Wno-undef silences that.
Use system zlib if available

Only fall back to miniz if we don't find zlib on the system. Distro
packagers like this much more, and we use code that has seen much
more testing. Incidentally, we've already had one case where miniz was
really slow on a 32 bit box.

Still keeping miniz as fallback for the rare platform/build box that
doesn't ship zlib, since waiting a few seconds for compressing the
backlog is still probably better than transmitting a few MB of extra
data...
Fix -Wundef warning

Was thrown on 32 bit, should be #ifdef instead of #if because the attribute
is only defined on 64 bit machines.
Silence yet another warning

I have no clue why neither gcc nor clang throw a -Wsign-compare for me
there, but do for some other people, so... *sigh*