output to a directory and URL prefix specified by settings
for local dev, this directory is served out via staticfiles
add blast+ to the image, so it can be run by the celery worker
add a URL endpoint, /submit_blast, which kicks off a BLAST job
add a URL endpoint, /blast_submission, which reports that status
of a BLAST job
BLAST is executed using the parameters provided by Andrew B.
Temporary FASTA files are written so that the chosen subset of the
database can be blasted against. The output of BLAST is read and
remapped against the OTU database to replace integers IDs with
the full OTU codes, working around maximum ID limit in BLAST.