Get statistics only for running containers. Fix #1281

Author: NITEMAN

plugins/docker/docker_

@@ -274,7 +274,7 @@ def get_container_stats(container, q):
 def parallel_container_stats(client):
     proc_list = []
     stats = {}
-    for container in client.all_containers:
+    for container in [ c for c in client.all_containers if c.status == 'running' ]:
         q = Queue()
         p = Process(target=get_container_stats, args=(container, q))
         proc_list.append({'proc': p, 'queue': q, 'container': container})