First draft for storing private data in native wuclasses.
Example of how to use this to count the number of switches in the light actuator (revert this commit before merging).
Revert "Example of how to use this to count the number of switches in the light actuator (revert this commit before merging)."

This reverts commit 2a7f82f035767f0a032599475c156d4611e7cb49.