update alignment filtering viz nb
update neighbor-joining nb
update region-specific ref collection nb
update pd nb
update pmsa nb
remove trailing empty cell from sft nb
update longest run nb
DOC: change 0.2.0 links to latest
update travis to use latest deps
Fix future.utils.six error
Merge pull request #35 from jairideout/skbio-0.2.1-update

Update recipes to use scikit-bio 0.2.1