fix issue 1695
minor comments edited
import from skbio 0.1.4
changelog merge conflict resolved
TST/REVERT: reduction of the runtime of the test, plus reversion of misguided attept at doing that yesterday
Merge pull request #1711 from gregcaporaso/issue-1710

TST/REVERT: reduction of the runtime of the test
Merge pull request #1702 from ekopylova/fix_1695

fix issue #1695
TST: added test of new functionality
Merge branch 'master' of github.com:qiime/qiime into issue-1707