Changed way service status is checked, so it generate less output.

README.md

@@ -2,12 +2,12 @@
 
 ## Sudo setup
 There are two commands needed for this to work:
-- `systemctl status isc-dhcp-server.service` to check if service does work
+- `systemctl is-active isc-dhcp-server.service` to check if service does work
 - `dhcp-lease-list --parsable` to get leases data
 
 ### Example sudoers configuration
 ```
-Cmnd_Alias SYSTEMD_STATUS_DHCPD=/usr/bin/systemctl status isc-dhcp-server.service
+Cmnd_Alias SYSTEMD_STATUS_DHCPD=/usr/bin/systemctl is-active isc-dhcp-server.service
 Cmnd_Alias DHCP_LEASE_LIST=/usr/sbin/dhcp-lease-list --parsable
 
 www-data        ALL= NOPASSWD: SYSTEMD_STATUS_DHCPD, DHCP_LEASE_LIST