make ConstantMapping work with custom URIs
Needed to provide licence information in commons as in gaurav/extraction-framework#7
try with URI, handles more cases
Disable validation for DOLCE namespaces
Fix for DBpedia classes not shown on overview page
Created a simple FileTypeExtractor that reports the file extension.
Changed file extensions to lowercase.
Updated FileTypeExtractor to use its own destination ("file_information") and its own property ("fileExtension").
Added a check for redirects in FileTypeExtractor.
Added a logging.warning for long extensions (>4 characters).
Updated the ontology.
Modified the FileTypeExtractor to emit dct:type and dct:format.
Updated FileTypeExtractor to use the dc:types in the DBpedia ontology.
Updated FileTypeExtractor to emit dc:type and rdf:type.
Improved documentation of FileTypeExtractorConfig.
Improved documentation and cleaned up code slightly.
Fixed some typing issues.
Moved image path generation into ExtractorUtils.
Updated ontology to include dbo:File and other classes FileTypeExtractor now needs.
Updated FileTypeExtractor and ImageExtractor to use a ExtractorUtils.getImageURL(Language, String) method.
Added source to an existing triple output.