testing.py: add some command-line options.

Created by: portnov

usage: testing.py [-h] [-t TEST [TEST ...]] [-o FILE.log] [-f] [-v] [-q] [--debug] [--info] [*.PY]

Run Sverchok tests

positional arguments:
  *.PY                  Test case files pattern

options:
  -h, --help            show this help message and exit
  -o FILE.log, --output FILE.log
                        Path to output log file
  -f, --fail-fast       Stop after first failing test
  -v, --verbose         Set the verbosity level
  -q, --quiet           Be quiet
  --debug               Enable debug logging
  --info                Log only information messages

Preflight checklist

Put an x letter in each brackets when you're done this item:

• Code changes complete.
• Code documentation complete.
• Documentation for users complete (or not required, if user never sees these changes).
• Manual testing done.
• Unit-tests implemented.
• Ready for merge.