.clang-format

run-tests: replace '/dev/null' with os.devnull for Windows

Many of the *.py tests were dying on:

    File "c:\Users\Matt\projects\hg\hgdemandimport\tracing.py", line 27, in log
      _pipe = open(os.environ['HGCATAPULTSERVERPIPE'], 'w', 1)
  IOError: [Errno 2] $ENOENT$: '/dev/null'

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IndentCaseLabels: false
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AllowShortFunctionsOnASingleLine: false
IncludeCategories:
  - Regex:           '^<'
    Priority:        1
  - Regex:           '^"'
    Priority:        2