BUG: timezone offset double counted using date_range
BUG: DateTimeIndex.append broken with tz-aware indices
BUG: Bug in DataFrame column insertion when the column creation fails, existing frame is left in
     an irrecoverable state (GH3010_)

DOC: tiny doc fix in io.rst
Merge pull request #3018 from jreback/insert_3010

BUG: Bug in DataFrame column insertion when the column creation fails (GH3010)
BUG: Bug in DataFrame update where non-specified values could cause dtype changes (GH3016_)
DOC: fix IPython snippet
BUG: Bug in user-facing take with negative indicies was incorrect producing incorrect  return values/failing (GH2892_)

BUG: extended negative indicies with take to generic.py (Panel/Series)

ENH: add out-of-bounds checking on use-facing take
Merge pull request #3021 from jreback/update_3016

BUG: Bug in DataFrame update where non-specified values could cause dtype changes
Merge pull request #3027 from jreback/take

BUG:  Bug in user-facing take with negative indicies was incorrect
BUG: Formatting of an index that has ``nan`` was inconsistent or wrong (would fill from
     other values), (GH2850_)

BUG: issue in test_index.py/test_format
       1) printing of 'nan' rather than the na_rep (NaN) is inconcistent
          with everywhere else
       2) a 'None' in the index is defacto treated as NaN, is this wrong?

CLN: constistency among index for NaN/NaT values
DOC: added cookbook.rst to main docs
DOC: more recipes
Merge pull request #3034 from jreback/set_index

BUG:  Formatting of an index that has nan was inconsistent or wrong
Merge pull request #3036 from jreback/cook

DOC: added cookbook.rst to main docs
BUG: Unstack of a frame with no nans would always cause dtype upcasting (GH2929_)
Merge pull request #2935 from stephenwlin/daterange_tz

BUG: timezone offset double counted using date_range and DateTimeIndex.append (fixes #2906, #2938)
BUG: Bug in DataFrame combine_first where non-specified values could cause dtype changes (GH3041_)
Merge pull request #3040 from jreback/unstack

BUG: Unstack of a frame with no nans would always cause dtype upcasting (GH #2929)
Merge pull request #3043 from jreback/combine_3016

BUG: frame combine_first where non-specified values could cause dtype changes (#3041)
BUG: Bug in groupby with first/last where dtypes could change (GH3041_)
DOC: docstring updates in core/common.py for _possibily_cast_to_timedelta