Retrieves all unique labels for the specified resource using the
the following priority order
http://eagle-i.org/ont/app/1.0/preferredLabel
http://purl.obolibrary.org/obo/IAO_0000111 (IAO preferred term)
rdfs:label
http://purl.obolibrary.org/obo/IAO_0000118 (IAO alternate term)
Walks the entire eagle-i data model by
starting with the set of "root resource" (top-level resource)
classes and traversing through object property relationships
and subclass relationships until every class and property
in the data model has been visited.