api returns a map of lists, rather than list of lists. The keys store reference sequence id (OTU id) of the original reference database
dict instead of map
Merge pull request #37 from ekopylova/sortmerna-api

update to sortmerna api
ENH: updated skbio dependency, fixes #38
Merge pull request #39 from gregcaporaso/issue-38

ENH: updated skbio dependency, fixes #38