Add support for validating subjects against AGROVOC

Checks values in the dc.subject or dcterms.subject field against the
AGROVOC REST API hosted by FAO. Code borrowed from agrovoc-lookup.py.

See: http://agrovoc.uniroma2.it/agrovoc/agrovoc/en/
See: https://github.com/ilri/DSpace/blob/5_x-prod/agrovoc-lookup.py

csv_metadata_quality/app.py

@@ -43,6 +43,11 @@ def main(argv):
         # Fix: duplicate metadata values
         df[column] = df[column].apply(fix.duplicates)
 
+        # Check: invalid AGROVOC subject
+        match = re.match(r'.*?dc\.subject.*$', column)
+        if match is not None:
+            df[column] = df[column].apply(check.agrovoc)
+
         # Check: invalid language
         match = re.match(r'^.*?language.*$', column)
         if match is not None: