------------------
* Added ``Event.thread``.
* Added ``Event.threadid`` and ``Event.threadname`` (available for filtering with ``Q`` objects).
* Added ``threading_support`` argument to ``hunter.trace``: makes new threads be traced and changes action output to include
threadname.
* Added support for using `pdb++ <https://pypi.python.org/pypi/pdbpp>`_ in the ``Debugger`` action.
* Added support for using `manhole <https://pypi.python.org/pypi/manhole>`_ via a new ``Manhole`` action.
* Made the ``handler`` a public but readonly property of ``Tracer`` objects.