Catch ValueError in option parsing

homer.py

@@ -982,7 +982,7 @@ if not monitoring:
                 mandatory_level = value
             else:
                 error("Unknown option %s" % option)
-    except getopt.error as reason:
+    except (getopt.error, ValueError) as reason:
         usage(reason)
         sys.exit(1)
     if delay is not None and multistreams: