py_trees_parser

[erichlf]

I have now released my xml py_trees_parser and thought you may want to know about it. Feel free to ask questions.

This will allow you to write a py_trees behavior tree using xml like so

<!-- The following example comes from
    https://py-trees-ros-tutorials.readthedocs.io/en/release-2.1.x/tutorials.html#tree -->
<py_trees.composites.Parallel name="TutorialOne"
  policy="$(py_trees.common.ParallelPolicy.SuccessOnAll(synchronise=False))">
  <py_trees.composites.Sequence name="Topics2BB" memory="$(False)">
    <py_trees_ros.battery.ToBlackboard name="Battery2BB"
      topic_name="/battery/state"
      qos_profile="$(py_trees_ros.utilities.qos_profile_unlatched())"
      threshold="30.0" />
  </py_trees.composites.Sequence>
  <py_trees.composites.Selector name="Tasks" memory="$(False)">
    <py_trees.behaviours.Running name="Idle" />
    <py_trees.behaviours.Periodic name="Flip Eggs" n="2" />
  </py_trees.composites.Selector>
</py_trees.composites.Parallel>

The end goal will be to have a gui that allows you to build a behavior tree.