Log Message:
Update to 1.4

Upstream changes:
CHANGES IN formatR VERSION 1.4

NEW FEATURES

  o `tidy_source()` can preserve line breaks in character strings in source code

MAJOR CHANGES

  o the deprecated functions tidy.source(), tidy.dir(), and tidy.eval() have
  been removed; use tidy_source(), tidy_dir() and tidy_eval() instead

  o comments that begin with `#+` or `#-` are no longer wrapped; such comments
  are treated as knitr chunk options in `knitr::spin()` (#52)

BUG FIXES

  o `tidy_source()` should not write an extra space to the last line of code
  (thanks, @mr-karan, #49)

  o long strings (> 1000 characters) in source code can be preserved now
  (thanks, @jholtman, #50)

  o `tidy_source()` might move any lines of code starting with `else` back to
  the previous lines (thanks, @Auburngrads, #51)