added scripts to parse drug->target mappings from drugbank
Merge remote-tracking branch 'gberriz/master'
pull some drug info from drugbank file
updated drugbank sha1; re-verify after download
dump of HGNC database

Equivalent to a custom download from
http://www.genenames.org/cgi-bin/hgnc_downloads, with the following
selections:

SELECT COLUMN DATA
  Curated by the HGNC
    HGNC ID
    Synonyms
    Gene Family Tag
    Approved Symbol
    Name Synonyms
    Approved Name
    Previous Symbols
    Accession Numbers
  Downloaded from external sources
    Uniprot ID
SELECT STATUS
  Approved