Add parent class potential

[l-emele]

Description of the issue

From today's OEKG meeting:

• add parent class potential for stock potential and flow potential
• add axiom between potential and spatial region

Ideas of solution

If you already have ideas for the solution describe them here

Workflow checklist

• I discussed the issue with someone else than me before working on a solution
• I already read the latest version of the workflow for this repository
• The goal of this ontology is clear to me

I am aware that

• every entry in the ontology should have a definition
• classes should arise from concepts rather than from words

[l-emele]

The existing classes flow potential and stock potential are defined as:

• A flow potential is a quantity value that describes the upper limit of an input or output of a process in a spatial region of reference per unit time.
• A stock potential is a quantity value that describes the upper limit of a stock of a source or sink in a spatial region of reference.

Thus I suggest: A potential is a quantity value that describes some upper limit in a spatial region of reference.

[stap-m]

We can use potential 'is about' some 'spatial region'.

[jannahastings]

@l-emele , @stap-m , we have a new team member @markus-rothkoetter and I wonder if we could assign the implementation of this issue to him as a first issue with your support ?

[l-emele]

I am fine with that and just assigned this issue to @markus-rothkoetter. I also think, that this issue is ready for implementation, as we discussed this issue in yesterday's OEKG meeting and the only thing left was a precise formulation of the definition, where I already got a thumbs up now.