Py-trees

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* [blackboard] convenience `absolute_name()` api for blackboard clients, `306 <https://github.com/splintered-reality/py_trees/pull/306>`_

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* [sequences] bugfix current child setting whilst moving through children, `304 <https://github.com/splintered-reality/py_trees/pull/304>`_

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* [behaviours] generators for variable values in SetBlackboardVariable, `300 <https://github.com/splintered-reality/py_trees/pull/300>`_

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* [behaviours] CheckBlackboardVariableValue, WaitForBlackboardVariableValue use comparison expressins, `296 <https://github.com/splintered-reality/py_trees/pull/296>`_
* [idioms] eternal_guard uses blackboard_names (previously blackboard_name_prefix), `295 <https://github.com/splintered-reality/py_trees/pull/295>`_
* [composites] Chooser deprecated, `293 <https://github.com/splintered-reality/py_trees/pull/293>`_
* [composites] chain-able add_children for all composites, `290 <https://github.com/splintered-reality/py_trees/pull/290>`_

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* [behaviours] generators for variable values in SetBlackboardVariable, `300 <https://github.com/splintered-reality/py_trees/pull/300>`_

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* [composites] fix current_child problems on dynamic child insertion/removal, `289 <https://github.com/splintered-reality/py_trees/pull/289>`_