Remove line in rc.local turning off eth0

* This line caused #60 due to change in naming of ethernet port interface with
Raspberry Pi 3 + Raspbian Stretch.
* Instead, we can turn off the networking service using systemctl while
preparing the image for release.

circlean_fs/root_partition/etc/rc.local

@@ -23,8 +23,6 @@ echo "GROOMER: end of boot, running rc.local."
 
 if [ -e /dev/sda ]; then
   if [ -e /dev/sdb ]; then
-    # Avoid possible misuse - turn off eth0 (ethernet port)
-    /sbin/ifconfig eth0 down
     trap clean EXIT TERM INT
     cd /opt/groomer
     /usr/sbin/led &