Parameter names in HTML manual pages were incorrectly replaced by
dashes. This seems to be the easiest fix.

documentation fixes

See merge request !404

Systemd optional journal

- This fixes #391, so the Knot DNS can be compiled with systemd and detect whether it should use systemd journal on runtime
- Add cascade check for libsystemd and only if not found it searches for libsystemd-daemon and libsystemd-journal, this is needed for backwards compatibility

See merge request !401

Search for unified libsystemd first then for older libsystemd-journal and libsystemd-daemon (Initial patch by Cameron Norman)

"That's one small step for man, one giant leap for mankind." -- Niel Armstrong

conf: add zone.zonefile_sync value -1 to never flush

See merge request !394

- print leading prompt
- don't quit when error