Update README to clarify core features

Author: mdesalvo

README.md

@@ -20,4 +20,4 @@ OWLSharp is a .NET library built atop <a href="https://github.com/mdesalvo/RDFSh
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-Along with core ontology features, it also includes a set of <a href="https://github.com/mdesalvo/OWLSharp.Extensions">extensions</a> for working with <b>LinkedData ontologies</b>!
+Along with core features, it also includes a set of <a href="https://github.com/mdesalvo/OWLSharp.Extensions">extensions</a> for working with <b>LinkedData ontologies</b>!