BUG: Bug in multi-index slicing with missing indexers (GH7866)
BUG/FIX: gut groupby.filter code, raise on multi-valued filter
Merge pull request #7871 from cpcloud/groupby-filter-fix

BUG/FIX: groupby should raise on multi-valued filter
Merge pull request #7867 from jreback/mi_loc

BUG: Bug in multi-index slicing with missing indexers (GH7866)
WIP: Index no longer an ndarray sub-class (GH5080)
CLN: add searchsorted to core/base (GH6712, GH7447, GH6469)
hopefully fix identity
fixup tests in test_timeseries for reverse ndarray/datetimeindex comparisons
add back groupby tests
fix groupby_frame_apply optimization