Bad commands throw stacktrace

[petermr]

Avoid stacktrace such as:

(base) pm286macbook:pyami pm286$ py4ami - h
usage: py4ami [-h] [--version] {DICT,GUI,HTML,PDF,PROJECT} ...
py4ami: error: argument command: invalid choice: '-' (choose from 'DICT', 'GUI', 'HTML', 'PDF', 'PROJECT')
Traceback (most recent call last):
  File "/opt/anaconda3/bin/py4ami", line 8, in <module>
    sys.exit(main())
  File "/opt/anaconda3/lib/python3.8/site-packages/py4ami/pyamix.py", line 1253, in main
    pyamix.run_command(sys.argv[1:])
  File "/opt/anaconda3/lib/python3.8/site-packages/py4ami/pyamix.py", line 342, in run_command
    self.parse_and_run_args(args)
  File "/opt/anaconda3/lib/python3.8/site-packages/py4ami/pyamix.py", line 357, in parse_and_run_args
    self.args = self.make_substitutions_create_arg_tuples(arglist, parser)
  File "/opt/anaconda3/lib/python3.8/site-packages/py4ami/pyamix.py", line 533, in make_substitutions_create_arg_tuples
    raise ValueError(f"bad command arguments {parsed_args} (see log output)")
ValueError: bad command arguments SystemExitFail_2 (see log output)
(base) pm286macbook:pyami pm286$ 

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