Using autopep8 (https://github.com/hhatto/autopep8) on all py files.
Some lines were changed manually (those which may change the logic).

Have not fixed E501 line too longs, these are the only pep8 failures.

Check current pep8 compliance of all py files in current directory:
for f in *.py; do pep8 $f; done

Run autopep8 on py files in current directory:
for f in *.py; do autopep8 -i $f; done
Reverted 4 test failures from autopep8 commit:
66fc98f0b7316331b505c4c4d4929fcbdc668d86

Arising from correcting PEP8 E712, changing == boolean to is boolean.
Possible that these are bugs in the tests?
shortened lines over 140 chars where appropriate
BUG: exclude non-numeric data from DataFrame.quantile #2625
DOC: release notes
ENH: enable pivot_table with more complex aggregation function and hack multiple level column unstacking into existing hierarchical columns. close #2643
DOC: release notes
Merge PR #2632
Use np.iinfo to figure out int min/max values
TST: unit test to reproduce #2599 on some platforms
TST: couple small test fixes
TST: randomize HDF5 file name to tease out #2645 issue