refact: separate converter classes from main program
separate downloadandconvert script
report number of unit entries with no <def>
separate downloadandconvert script
more complete conversion, but still needs adjustments (like, use common classes/props across the various vocabs)
capture base definitions separately
as a workaround for a rendering limitation in the ORR, make basedefs's namespace equal to that of the vocabulary
add all baseDefs statements to each vocabulary so it's more self-contained (and "friendlier" to ORR display capability)
put prefix-related definitions in BaseDefs and use them in prefix conversion
put prefix-related definitions in BaseDefs and use them in prefix conversion
#2 first singular name is now taken when no def is associated with unit; similar handling with it, that is, hash code for the id of the Unit instance.
general update, including use of an application.conf for all program parameters, and generation of ontology entry to capture metadata; also, first version of all RDFs with "mmi" authority.
minor code adjustments (no changes in generated RDF files)
fix #9 : for each vocab, include only relevant base definitions