Added RFC to BibTeX option to the drop-down menu of the id-based entry generator section
of the new entry dialog. The RFC fetcher accepts entrys that include or exclude the
rfc prefix. BibTex data is retreived from 'https://datatracker.ietf.org'
(e.g. https://datatracker.ietf.org/doc/rfc1945/bibtex/'). A test for the fetcher is included;
.

Add RFC fetcher that obtains more accurate BibTeX data
than the DOI fetcher, includes test cases.

Add RFC fetcher that obtains more accurate BibTeX data
than the DOI fetcher, includes test cases.