BLD: install older versions of numexpr/pytables on fulldeps/2 build
Merge pull request #3891 from jreback/hdf_bld

BLD: install older versions of numexpr/pytables on fulldeps/2 build
DOC: minor io.rst edits
TST: json tests to int64 to avoid dtype issues
TST: skip tests if xlrd has lower than needed version
TST: skip pickle tests on not-little endianess
TST: skip test_encoding on non-little endian in test_pytables
TST: skip some stata tests on non-little endian
TST: convered skips on knownfailures to knownfailures (test_pickle/test_stata)
Merge pull request #3898 from jreback/test_fixes

TST: test fixes for various builds (debian)
TST: convert knowntestfailures to skip tests
Merge pull request #3906 from jreback/test_fix2

TST: convert knowntestfailures to skip tests
BUG: fix unicode -> str cast in tslib

This should use format since calling str on a unicode string is a *bad* idea
because it may or may not repr correctly.
Merge pull request #3900 from cpcloud/tslib-fix

BUG: fix unicode -> str cast in tslib
CLN depreciate save&load in favour of to_pickle&read_pickle

DOC replace save&load with to_pickle&read_pickle
FIX not mention save/load being removed