- issue2551275 - Allow configuring max_children in roundup-server. new -m and --max_children command line arguments and max_children config file setting for roundup_server.py/roundup-server. CHANGES.txt, admin_guide.txt, roundup-server.1 updated.

try:
    # Python 3+
    from time import perf_counter
except (ImportError, AttributeError):
    # Python 2.5-2.7
    from time import clock as perf_counter   # noqa: F401