DOIs for organizing scrapers

[petermr]

Scrapers can be organized by publisher or publisher DOIs so that we avoid duplication and can easily search. Suggest a syntax with DOI first and mnemonic suffixed. Example:
PLOSONE is 10.1371/journal.pone
scraper would be indexed under
10_1371_pone
An article in BMC evolutionary biology is
10.1186/1471-2148-14-70
so suggest
10_1186_bmc
if there are per-journal scraper they could be appended
10_1186_bmc_evolutionary_biology
(There used to be a unique CODEN for journals but I think this has disappeared)