BUG: don't allow an empty dataframe to have scalar assignment succeed (GH5744)
Merge pull request #5745 from jreback/empty_frame2

BUG: don't allow an empty dataframe to have scalar assignment succeed (GH5744)
API/REGRESS: partial revert of f8b6208675b5b10d73a74f50478fa5e37b43fc02
     allow assignment of a column in a frame with a scalar with no index (so adds to the columns),
     instead of raising; this preservers 0.12 behavior
Merge pull request #5747 from jreback/empty_frame3

API/REGRESS: partial revert of f8b6208675b5b10d73a74f50478fa5e37b43fc02 (GH5720,GH5744)
DOC: added missing argument in Series.apply
DOC: io.rst top-level can now click on read/write methods to acess the appropriate sections

DOC: cleaned v0.13.txt
Merge pull request #5750 from mortada/series_apply

DOC: added missing argument in Series.apply
ENH: set display.max_seq_items default != None
BUG: construction of DataFrame from empty Series regression (GH5756)
BUG: Row-wise concat of differeing dtypes failing in certain cases (GH5754)
Merge pull request #5757 from jreback/fixes

BUG: empty Series construction (GH5756), concat issues (GH5754)
API: Series.ravel compat with ndarray
Merge pull request #5759 from jreback/ravel

API: Series.ravel compat with ndarray
Merge pull request #5753 from y-p/PR_max_seq_items

ENH: set display.max_seq_items default != None
DOC: remove travis mentions in CONTRIBUTING.md. It just works now.