k-mer signatures for a selection of 25 real bacterial genomes. 15 genomes are
from E. coli, 5 are from Staphylococcus aureus, and 5 are from Streptococcus
pneumoniae. Used k-mer spec ATGAC/11.

Files:

* accs.txt -- accession numbers of genomes, one per line.
* signatures.pickle -- pickled list of numpy arrays containing k-mer signatures in
  sparse format.
