BUG: fix metacharacter replacement bug in DataFrame.replace()
Merge pull request #6778 from cpcloud/regex-false-replace

BUG: fix metacharacter replacement bug in DataFrame.replace()
BUG: bug in timedelta ops on 32-bit platforms (GH6808)
BUG/ENH: Fix to_excel representation of inf values
Merge pull request #6812 from jtratner/excel-inf

BUG/ENH: Fix to_excel representation of inf values
BUG/API: disallow boolean arithmetic operations
CLN/TST: move ops test from test_frame.py to test_expressions.py
BUG: check for dtype attr then check block types if no dtype attr
Merge pull request #6803 from cpcloud/bool-arith-ops-6762

BUG/API: disallow boolean arithmetic operations
ENH: added nunique and value_counts functions to Index
Merge pull request #6734 from sinhrks/ind_nunique

ENH: added nunique function to Index
BLD: spring cleaning on Makefile