Added exit command mention

Author: jamtur01

website/source/docs/commands/console.html.markdown

@@ -34,6 +34,9 @@ The command-line flags are all optional. The list of available flags are:
 * `-state=path` - Path to the state file. Defaults to "terraform.tfstate".
   A state file doesn't need to exist.
 
+You can close the console with the `exit` command or by using Control-C
+or Control-D.
+
 ## Scripting
 
 The `terraform console` command can be used in non-interactive scripts