LOV crawler & Vaadin update

[chile12]

• Updated Vaadin, since it caused multiple issues especially under windows.
• Included an 'Ontology' option in the constraint selection, which will not skip owl, rdf, and rdfs constraints tests.
• Made the excluded ontologies configurable, (by default it still excludes owl, rdf, rdfs), introducing an 'x' option in the CLI.
• Revised the LOV endpoint class, and created basically a crawler, which searches actively for possible resource locations, I also updated the default schemaDecl.csv
• I introduced a directoary containing standard vocabularies which are always loaded (based on vann properties (containing rut, shacl, and xsd as ontology with regex restrictions)
• SchemaSource now collects all imports transitively, a special function now can also load the source with all its imports.
• other minor stuff

How Has This Been Tested?

• added a test for the LOV crawler (deactivated by default)
• added xsd type tests
• added a test for imported ontologies

Types of changes

• [x] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• [x] My code follows the code style of this project.
• [ ] My change requires a change to the documentation.
• [ ] I have updated the documentation accordingly.
• [x] I have added tests to cover my changes.
• [x] All new and existing tests passed.

[coveralls]

Coverage decreased (-2.2%) to 55.936% when pulling 9281c12223f59876f440829be6f2b947c8fb3529 on fix/updateVaadin into d96c328f15fb21dd914d6cd0bae64398a8a3314d on master.

[jimkont]

:100: thanks a lot @chile12