Using someValuesFrom here is redundant and overly complex, since the property
range specifies that it is for literals anyway.  So, simply replace it with a
minCardinality of 1.

It is more or less meaningless to have an explicit type of rdfs:Resource, and
some tools don't like it, since everything (including classes and properties)
is a Resource.  Since this is an individual, owl:Thing is a better type.

This was obviously wrong.  I'm not sure how this happened, probably a
copy/paste mistake.

These are required by OWL tools to use vocabulary from another ontology.
Though we don't use OWL tools in LV2, they are at least useful for sanity
checking the semantic side of things.  These properties are also nice to have
anyway, since they clearly describe the dependencies between specifications.