Add the docker.socket back in

Re-adds the docker.socket file for debian based distributions.

Signed-off-by: Eli Uriegas <eli.uriegas@docker.com>

contrib/init/systemd/docker.service

@@ -10,7 +10,7 @@ Type=notify
 # the default is not to use systemd for cgroups because the delegate issues still
 # exists and systemd currently does not support the cgroup feature set required
 # for containers run by docker
-ExecStart=/usr/bin/dockerd -H unix://
+ExecStart=/usr/bin/dockerd
 ExecReload=/bin/kill -s HUP $MAINPID
 TimeoutSec=0
 RestartSec=2

contrib/init/systemd/docker.socket

@@ -0,0 +1,12 @@
+[Unit]
+Description=Docker Socket for the API
+PartOf=docker.service
+
+[Socket]
+ListenStream=/var/run/docker.sock
+SocketMode=0660
+SocketUser=root
+SocketGroup=docker
+
+[Install]
+WantedBy=sockets.target

systemd/00-socket-activation.conf

@@ -0,0 +1,7 @@
+[Unit]
+After=docker.socket
+Requires=docker.socket
+
+[Service]
+ExecStart=
+ExecStart=/usr/bin/dockerd -H fd://