Refactor index-as-string groupby tests and fix spurious warning (Bug 17383)#17843

Merged

jreback merged 5 commits intopandas-dev:masterfrom

jonmmease:bug_17383

Oct 14, 2017

Commits on Oct 10, 2017

Refactor groupby tests for using strings to reference index levels
Jon M. Mease
committed
Fix for GH17383
Jon M. Mease
committed
Added whatsnew entry
Jon M. Mease
committed
Missed comment update during refactor
Jon M. Mease
committed

Commits on Oct 13, 2017

Parameterize and fixturize tests
Jon M. Mease
committed