Added command for ssh into swarm manager (#560)

engine/swarm/swarm-tutorial/create-swarm.md

@@ -10,6 +10,10 @@ machines.
 
 1. Open a terminal and ssh into the machine where you want to run your manager
 node. For example, the tutorial uses a machine named `manager1`.
+    
+    ```bash
+    docker-machine ssh manager1
+    ```
 
 2.  Run the following command to create a new swarm:
 
@@ -84,4 +88,4 @@ node. For example, the tutorial uses a machine named `manager1`.
 ## What's next?
 
 In the next section of the tutorial, we'll [add two more nodes](add-nodes.md) to
-the cluster.
+the cluster.