Restructure inheritance control stack components

Issue spawned based of an offline discussion on 27/05/2021 between @AdriaanRol, @jgloudemans and @dcrielaard resulting from !70 (comment 587063764).

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Currently, the cs component is expected to inherit from the QCoDeS driver to allow it to control the hardware while allowing explicit control over all the parameters in a way that is easily understandable by the end user.

It is now deemed preferable anyway to have the cs component hold a reference to the driver object instead. Possibly through QCoDeS' InstrumentRefParameter.