* [RDF_SERIAL,EXT] AP predicate throws exception when there are no RDF files to convert.
* [RDF_SERIAL,FIX] Converting to the same serialization format can be legitimate (since serialization implementations differ), so check for a different file name now i.o. only a different file extension.
* [HTML_AP_TERM,HTML_PL_TERM,EXT] Support for multiple name-value pairs.
* [RDF_META,NEW] New module, recently delete, but now back in a simplified form.
* [RDF_SERIAL,SC] Simplified code by using RDF_META.