Add basic validator

[nicholascar]

• adds a basic SHACL validator for the Prof Vocab
• adds tests for the validator
• removes old, incomplete, SHACL shapes

Closes #54

[ajnelson-nist]

Hi @nicholascar ,

As part of my work in the SHACL 1.2 Profiling Task Force, I've also tried writing a similar validator to this graph. So, I have some opportunity to compare results with you.

These two highlighted shapes surprised me. I would have written the same (modulo IRI) if I saw owl:disjointWith statements in the prof Turtle graph, but I don't see them in today's code-state:

dx-prof/prof/rdf/prof.ttl

Lines 141 to 145 in de5b96a

	### http://www.w3.org/ns/dx/prof/ResourceDescriptor
	:ResourceDescriptor rdf:type owl:Class ;
	rdfs:label "Resource Descriptor"@en ;
	skos:definition "A description of a resource that defines an aspect - a particular part, feature or role - of a Profile"@en ;
	skos:usageNote "Can be use to indicate the formalism (via dct:format) and any adherence to a dct:Standard (via dct:conformsTo) to allow for machine mediation as well as its purpose via relation to a ResourceRole (via hasRole)"@en .

dx-prof/prof/rdf/prof.ttl

Lines 156 to 163 in de5b96a

	### http://www.w3.org/ns/dx/prof/Profile
	:Profile rdf:type owl:Class ;
	rdfs:subClassOf dct:Standard ;
	dct:source <https://www.w3.org/2017/dxwg/wiki/ProfileContext> ;
	rdfs:label "Profile" ;
	skos:definition """A specification that constrains, extends, combines, or provides guidance or explanation about the usage of other specifications.
	This definition includes what are often called \"application profiles\", \"metadata application profiles\", or \"metadata profiles\"."""@en .

So, if these shapes are to be added, shouldn't prof.ttl receive an update to declare the classes owl:disjointWith one another?

[ajnelson-nist]

Similar to my discovery path on the above remark, I would have encoded this cardinality restraint if I had seen it in today's code-state of prof.ttl.

So, shouldn't prof.ttl also receive an update adding:

:ResourceDescriptor
  rdfs:subClassOf [
    a owl:Restriction ;
    owl:onProperty prof:hasRole ;
    owl:cardinality "1"^^xsd:nonNegativeInteger ;
  ] ;
  rdfs:subClassOf [
    a owl:Restriction ;
    owl:onProperty prof:hasArtifact ;
    owl:cardinality "1"^^xsd:nonNegativeInteger ;
  ] ;
  .