BUG: MPL Plot cannot make loglog option worked
DOC: minor documenation changes
Merge pull request #6722 from sinhrks/loglog

BUG: MPLPlot cannot make loglog keyword worked
API: all offset operations now return Timestamp types (rather than datetime), Business/Week frequencies were incorrect (GH4069)
Merge pull request #6743 from jreback/freq

API: all offset operations now return Timestamp types (rather than datetime) (GH4069)
TST: windows dtype correction
PRF: .shift() speedup: Only pass in c_contiguous arrays to np.roll/take
PRF: Fixed shift speed tests and added consolidated DataFrame shift perf
test
Merge pull request #6747 from dalejung/quick_shift_fixes

Quick shift fixes