title: Can i configure pytest to ignore directories when it's running with --looponfail option?
body: <p>I have a directory with a unittest-module and a <code>logs</code>-directory where debug-informations are written.
  since I use the <code>-f</code> / <code>--looponfail</code> option, I need changes in the <code>logs</code>-directory to be ignored.</p>
  
  <pre><code>tests$ ls
  logs  __pycache__  pytest.ini  test_basic.py
  
  tests$ cat pytest.ini
  [pytest]
  norecursedirs = logs
  python_files = test_*.py
  
  tests$ py.test -h
  (...)
  [pytest] ini-options in the next pytest.ini|tox.ini|setup.cfg file:
  
    markers (linelist)       markers for test functions
    norecursedirs (args)     directory patterns to avoid for recursion
    usefixtures (args)       list of default fixtures to be used with this project
    python_files (args)      glob-style file patterns for Python test module discovery
    python_classes (args)    prefixes for Python test class discovery
    python_functions (args)  prefixes for Python test function and method discovery
    addopts (args)           extra command line options
    minversion (string)      minimally required pytest version
    rsyncdirs (pathlist)     list of (relative) paths to be rsynced for remote distributed testing.
    rsyncignore (pathlist)   list of (relative) glob-style paths to be ignored for rsyncing.
    looponfailroots (pathlist) directories to check for changes
  </code></pre>
  
  <p>Eventually the failing test is invoked in a loop, because changes in <code>logs/test_basic.log</code> are monitored and I wonder why this is so.  The <a href="http://pytest.org/latest/customize.html" rel="noreferrer">documentation</a> seems clear to me.</p>