Py-trees

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* [mock] server bugfixed to accommodate custom result handlers, `154 <https://github.com/splintered-reality/py_trees_ros/pull/154>`_

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* [behaviours] default to periodic checks with warnings for action client timeouts, `153 <https://github.com/splintered-reality/py_trees_ros/pull/153>`_

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* [behaviours] wait_for_server_timeout_sec in action clients, `152 <https://github.com/splintered-reality/py_trees_ros/pull/152>`_
* [trees] avoid irregular snapshot streams by avoiding timing jitter, `151 <https://github.com/splintered-reality/py_trees_ros/pull/151>`_

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* [programs] graph discovery timeouts 1.0->2.0s, `149 <https://github.com/splintered-reality/py_trees_ros/pull/149>`_

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* [behaviours] action client goals from blackboard behaviour, `148 <https://github.com/splintered-reality/py_trees_ros/pull/148>`_
* [behaviours] publish from blackboard behaviour, `146 <https://github.com/splintered-reality/py_trees_ros/pull/146>`_

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* [serialisation] include parallel policy details