Handle mount process crash gracefully.

main.go

@@ -265,6 +265,10 @@ func (d *ofsDriver) Mount(r *volume.MountRequest) (*volume.MountResponse, error)
 			}
 			cmd.Wait()
 			log.WithFields(log.Fields{"name": r.Name}).Info("Completed mount process")
+
+			// In case the mount stopped in unplanned fashion allow easy re-mount
+			rt.mounted = false
+			rt.use = make(map[string]bool)
 		}()
 		if err := cmd.Start(); err != nil {
 			return &volume.MountResponse{}, fmt.Errorf("unexpected error mounting '%s' error: %s", r.Name, err.Error())