ENH: HDFStore will retain index attributes (freq,tz,name) on recreation (GH3499_)

TST: added legacy_table_0.11 table and tests
ENH: support timezone data_columns in HDFStore (GH2852)

DOC: update release notes/whatsnew, added whatsnew 0.11.1 to index.rst

ENH: warn a FrequencyWarning if appending with a different frequency that existing
Merge pull request #3531 from jreback/hdf_bug

ENH: HDFStore enhancements