Now all invocations have following order of arguments (if present):

    addgroup -S -g ... GROUP
    adduser -S -u ... -D -H -h ... -s ... -G ... -g ... USER

Following rules have been applied:
- script starts with shebang !#/bin/sh followed by blank line,
- script ends with exit 0 prepended by blank line,
- only stderr of adduser, addgroup or passwd is redirected to /dev/null,
- getent passwd/group instances has been removed,
- manual checking of file and group existence has been removed,
- `|| true` instances has been removed.

Comments and line wrapping have been preserved.

This way we can avoid ugly default:

    Linux user,,,

Groups and users created by packages shouldn't use high ids by default
(unless explicitly requested), to distinguish them from groups and users
created by administrators for humans.

Following 41 files lacked -S next to addgroup:
- community/sword/sword.pre-install
- main/amavisd-new/amavisd-new.pre-install
- main/chrony/chrony.pre-install
- main/cvechecker/cvechecker.pre-install
- main/dnsmasq/dnsmasq.pre-install
- main/freeradius/freeradius.pre-install
- main/gdnsd/gdnsd.pre-install
- main/haproxy/haproxy.pre-install
- main/haproxy/haproxy.pre-upgrade
- main/kamailio/kamailio.pre-install
- main/logcheck/logcheck.pre-install
- main/mlmmj/mlmmj.pre-install
- main/nrpe/nrpe.pre-install
- main/open-vm-tools/open-vm-tools.pre-install
- main/postgrey/postgrey.pre-install
- main/privoxy/privoxy.pre-install
- main/redis/redis.pre-install
- main/samba/winbind.pre-install
- main/sircbot/sircbot.pre-install
- main/smokeping/smokeping.pre-install
- main/squark/squark.post-install
- main/squid/squid.pre-install
- main/squid/squid.pre-upgrade
- main/subversion/subversion.pre-install
- main/trac/trac.pre-install
- main/vsftpd/vsftpd.pre-install
- main/zabbix/zabbix-agent.pre-install
- testing/3proxy/3proxy.pre-install
- testing/cluster-glue/cluster-glue.pre-install
- testing/elasticsearch/elasticsearch.pre-install
- testing/emby/emby.pre-install
- testing/gdnsd/gdnsd.pre-install
- testing/icinga2/icinga2.pre-install
- testing/lusca/lusca.pre-install
- testing/lusca/lusca.pre-upgrade
- testing/mongodb/mongodb.pre-install
- testing/openxcap/openxcap.pre-install
- testing/prosody/prosody.pre-install
- testing/rancid/rancid.pre-install
- testing/rutorrent/rutorrent.pre-install
- testing/zabbix/zabbix-agent.pre-install

Following 60 files lacked -S next to adduser:
- community/caddy/caddy.pre-install
- community/domoticz/domoticz.pre-install
- community/minetest/minetest-server.pre-install
- community/oscam/oscam.pre-install
- community/seafile/seafile-server.pre-install
- community/syncthing/syncthing.pre-install
- main/apache2/apache2.pre-install
- main/aports-build/aports-build.pre-install
- main/atheme-iris/atheme-iris.pre-install
- main/bind/bind.pre-install
- main/clamav/clamav-db.pre-install
- main/clamsmtp/clamsmtp.pre-install
- main/clamsmtp/clamsmtp.pre-upgrade
- main/coova-chilli/coova-chilli.pre-install
- main/cvechecker/cvechecker.pre-install
- main/dhcp/dhcp.pre-install
- main/distcc/distcc.pre-install
- main/djbdns/dnscache.pre-install
- main/djbdns/tinydns.pre-install
- main/dovecot/dovecot.pre-install
- main/ez-ipupdate/ez-ipupdate.pre-install
- main/fetchmail/fetchmail.pre-install
- main/freeswitch/freeswitch.pre-install
- main/gitolite/gitolite.pre-install
- main/gnats/gnats.pre-install
- main/gross/gross.pre-install
- main/icecast/icecast.pre-install
- main/kamailio/kamailio.pre-install
- main/lighttpd/lighttpd.pre-install
- main/mariadb/mariadb.pre-install
- main/memcached/memcached.pre-install
- main/ngircd/ngircd.pre-install
- main/nrpe/nrpe.pre-install
- main/openntpd/openntpd.pre-install
- main/postgrey/postgrey.pre-install
- main/snort/snort.pre-install
- main/squid/squid.pre-install
- main/squid/squid.pre-upgrade
- main/subversion/subversion.pre-install
- main/trac/trac.pre-install
- main/transmission/transmission-daemon.pre-install
- main/ympd/ympd.pre-install
- main/znc/znc.pre-install
- testing/at/at.pre-install
- testing/buildbot-slave/buildbot-slave.pre-install
- testing/buildbot/buildbot.pre-install
- testing/clapf/clapf.pre-install
- testing/cluster-glue/cluster-glue.pre-install
- testing/dbmail/dbmail.pre-install
- testing/dspam/dspam.pre-install
- testing/ejabberd/ejabberd.pre-install
- testing/emby/emby.pre-install
- testing/mongodb/mongodb.pre-install
- testing/opensips/opensips.pre-install
- testing/pdns/pdns.pre-install
- testing/prosody/prosody.pre-install
- testing/qpage/qpage.pre-install
- testing/rrdbot/rrdbot.pre-install
- testing/wt/wt.pre-install
- unmaintained/ejabberd-git/ejabberd-git.pre-install

fix #5299

Things to be complete:
1. Build is only for x86_64, because I have to made a few hacks in code.
Most critical one is __ELF_NATIVE_CLASS
2. No tc-malloc. It doesnt build, so system allocator instead. Im working
on gpreftools package...
3. No heap usage statistics: always returns 0. It is broken in mongodb for
64bit architecture and also musl mallocinfo is not compatible with glibc.
So I just comment out heap reporting code, see comments in APKBUILD
4. Use more system libs, yaml & boost are from the top of my mind. Boost
make compilation fails, but should be easy to fix
5. Enable mongodb tests during build. Im just not sure how that should be
done in Alpine, i.e _where_ in build lifecycle tests should run