Add support for nested_structures>=0.4
Add support for nested_structures>=0.4

Add support for `nested_structures>=0.4`, which passes the following
additional arguments to the call-back functions:

 - `first`: `True` if the node is the first child.
 - `last`: `True` if the node is the last child.
 - `depth`: The 0-indexed depth of the node in the traversal.

wheeler-microfluidics/dmf_control_board_plugin