Improve command module and add "schedule" command group

none/argparse.py

@@ -0,0 +1,16 @@
+from argparse import *
+
+
+class ParserExit(RuntimeError):
+    def __init__(self, status=0, message=None):
+        self.status = status
+        self.message = message
+
+
+class ArgumentParser(ArgumentParser):
+    def _print_message(self, *args, **kwargs):
+        # do nothing
+        pass
+
+    def exit(self, status=0, message=None):
+        raise ParserExit(status=status, message=message)