- Bump to version 22

- Make sure that (future) users of %sysctl_apply() and %binfmt_apply() will call
the macros with arguments.

- Test the presence of /run/systemd/system to check whether we're operating
during transactional updates. Hence the behavior is the same when operating in
a chroot or during transactional updates.
- Leave %sysctl_apply() and %binfmt_apply() empty (bsc#1211272)
Only the former has very few users currently and none of them has specific
code relying on the new sysctl values to be effective between the macros and
the file triggers.

- Bump to version 21

- Rely on 'systemd-update-helper' shell script to implement %service_* macros
The helper was introduced by upstream commit 6d825ab2d42d3219e49a1. The main
advantage is that we no more need to rebuild all packages to update the macro
definitions.
Internally the script relies on file triggers for 'daemon-reload' operations
and for restarting units (when needed).
- Update other macros to reflect the fact that systemd package provides file
triggers for sysusers, tmpfiles, hwdb, and journal catalog.