Behavior implementation that maps input from an array of InputDevice objects
to Action objects, which are then processed by the encapsulating Participant.
Calls load(base) on each InputDevice in the array of devices, using a
sub-node named according to the device's unique ID (see the getID()
method) and that device's order among those devices with an identical ID.
Calls store(Hierarchy) on each InputDevice in the array of devices,
using a sub-node named according to the device's unique ID (see the
getID() method) and that device's order among those devices with an
identical ID.