Add implementations of free to BaseCClass classes

[valentin-krasontovitsch]

For some reason semeio tests are failing, and among other things throwing an exception about something based on BaseCClass not implementing free. I cannot tell from the logs which class it is, hence we search for all classes (directly) based on BaseCClass, and add a free method, hoping that this will alleviate the errors we're seeing.

Issue Resolves #my_issue

Approach Short description of the approach

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