Stopping service fails to stop gluster native event handler cherrypy server

[r0h4n]

Link: https://github.com/Tendrl/gluster-integration/blob/master/tendrl/gluster_integration/message/gluster_native_message_handler.py#L126

When tendrl-gluster-integration service is stopped, it fails to stop the gluster native event handler cherrypy server, this needs to be fixed