Check nickserver process with systemctl status

leap test didn't catch the right process name:

00:25:19  = [citest3066] FAIL: Webapp > Are daemons running? [webapp.rb:31]:
00:25:19  = [citest3066]   No running process for ^/usr/bin/ruby /usr/bin/nickserver

because it was runnign as 'ruby /usr/bin/nickserver' - we should write a proper unit file and check with "systemctl status nickserver".

(from redmine: created on 2016-11-09, relates #8578 (closed))