Use the PermissionsStartOnly systemd option to apply the permission
related configurations only to the start command. This allows us to stop
using "sudo" for ExecStartPre and ExecStopPost hooks and drop the
"requiretty" /etc/sudoers hack from Scylla's RPM.
Tested-by: Takuya ASADA <syuu@scylladb.com>
Message-Id: <1466407587-31734-1-git-send-email-penberg@scylladb.com>
(cherry picked from commit 1d5f7be447)