pubmed-central-affiliations

1. fetch-pubmed.php (fetch all PubMed records for PMC articles)
2. parse-pubmed.php (parse affiliations and PMC IDs out of PubMed records)
3. fetch-pmc.php (fetch PMC front-matter records for each article with a PMC ID)
4. parse-pmc.php (parse affiliation emails out of PMC front-matter records)