PERF: optimize index.__getitem__ for slice & boolean mask indexers
Merge pull request #6440 from immerrr/index-getitem-performance

PERF: optimize index.__getitem__ for slice & boolean mask indexers
BLD: add benchmarks for all loc/iloc indexers for Series, DataFrame & Panel
BLD: don't contract stats output if it's longer than 60 rows
BLD: fix indexing__* benchmarks to work in comparative mode