Fixes NIF-8920. This update fixes these issues in NIF-8920

 * synonyms are distinct xml elements in the former. Relegated to "other properties" in the latter
 * definitions are relegated to comments
Fixes #36. Attribuite "property" is added to the <synonym> element. This attribute tells whether it is a broad/narrow/axact or other sysnonyms.
Fixes #36. Attribuite "property" is added to the <synonym> element. This attribute tells whether it is a broad/narrow/axact or other sysnonyms.
Enable searching on URI for function "concepts/"