LP #713820: Remove docstrings from various methods in ZCatalog, as they shouldn't be web-publishable.

See https://bugs.launchpad.net/zope2/+bug/713253/

accumulating successive prints of stats.

Control_Panel/DebugInfo/manage_profile ZMI view.  This has been
available since Python 2.5 and we no longer support Python 2.4 so
there's little reason not to use the faster profiler.

Control_Panel/DebugInfo/manage_profile ZMI view has been broken since
Python 2.5.  This breaks Python 2.4 compatibility when the
publisher-profile-file configuration option is set.  This also removes
some ugly sys.stdout hackery.

LP #659968: Added support for level argument to the ``__import__`` function as introduced in Python 2.5. Currently only level=0 is supported.