arranged chartsview so keys are added to get_context_data as they are calculated for greater clarity, not all at the end

replaced isbn template tag filtering with get_title_or_isbn, which refers to saved isbn metadata, rather than making a new API call with each page request

ISNBMetadata utility revised to use Internet Archive's OpenLibrary, rather than WorldCat, which is now a paid service

removed extraneous whitespace, and unnecessary context_object_names when default works (all models except bidflags), as well as redundant template_suffix_names