Improve unit representation in EMMO

[markdoerr]

Please revise unit representation in EMMO:

There is a long (arbitrary) list of derived units, like "ElectricPotentialPerTemperatureUnit", "ElectricPotentialPerTimeUnit", ... which could be infinitely extended by all combinatoric combinations.

(There are also an arbitrary (?) list of non-SI units).

To keep EMMO compact, wouldn't it make sense to restrict the ontology to base SI units only ? (Everything could be derived from them)

Please also keep in mind simple competency questions, that should be easily answerable with SPARQL queries, like "Which SI unit has the length measurement ?"