BUG: ewm*() interpretation of min_periods is off by one
BUG: do not assume 0 is in index of potential Series
TST/BUG: Rename html encoding test files.

html test_encode fails on OSX due to missing dash in ‘utf32’ encoding
string.
Merge pull request #7902 from toobaz/_get_array_list

BUG: do not assume 0 is in index of potential Series
Merge pull request #7903 from jmorris0x0/osx-html-encode-bugfix

TST/BUG: Rename html encoding test files.
Merge pull request #7898 from seth-p/ewm_min_periods_off_by_one

BUG: ewm*() interpretation of min_periods is off by one
TST: make removal tests exact for test_pytables
ENH: Add BusinessHour offset