Update between.cpp

typo
Set the row.names by the first non-short length

Before this was always using the first length, which resulted in the
data.frame being truncated if the first argument was a length 1 vector
to be recycled.

Fixes #680
Add note to news
Simplify logic for NA length
context is not capitalized
Add a few more data_frame tests

This is mostly to get Travis to retry the build.
Fix extraneous parenthesis.
Extra whitespace

hopefully travis will run correctly this time :-/
doc fix.
doc fix
hybrid min_rank correctly handles NaN only columns. closes #726
`first` and `last` correctly promote factors, dates and times (#509).
`inner_join` no longer reorders (#684).
`DataFrameVisitors` handles data frames as columns of data frames, recursively. (#602)
joining factors whose levels are not identical (same levels, same order) generates
  a warning and coerces to character (closes #684). Same when joining a character vector
  with a factor and vice versa.
`rbind_list` fails to combine `INTSXP` and `factor` (closes #751)
`min(.,na.rm = TRUE)` did not handle `Date` encoded as `REALSXP`.  closes #755
data frames and matrices as column of data frame processed by verbs
  generates an error. (0.3.1 part of #602).
some more #602 related tidying things up
allow data frame columns again