process download_taxonomy_db: taxdump and prot_accession2taxid
If the user has already downloaded
ftp://ftp.ncbi.nih.gov/pub/taxonomy/accession2taxid/prot.accession2taxid.gz
and ftp://ftp.ncbi.nih.gov/pub/taxonomy/taxdump.tar.gz
--> it must be possible to skip download_taxonomy_db
process and put directly these two files in input of diamond_parser
process.
TIP: when the user knows that he will launch the pipeline multiple times: it will be usefull that he downloads once these two files to use it multiple times because they took disk space.