Backup plugins directory (#297)

contrib/aws/Dockerrun.aws.json

@@ -19,6 +19,12 @@
                 "sourcePath": "/var/app/current/app/mattermost/logs"
             }
         },
+        {
+            "name": "app-plugins",
+            "host": {
+                "sourcePath": "/var/app/current/app/mattermost/plugins"
+            }
+        },
         {
             "name": "db-data",
             "host": {
@@ -72,6 +78,10 @@
                 {
                     "sourceVolume": "app-logs",
                     "containerPath": "/mattermost/logs"
+                },
+                {
+                    "sourceVolume": "app-plugins",
+                    "containerPath": "/mattermost/plugins"
                 }
             ],
             "links": [