Work around D Mode void-function error

See https://github.com/Emacs-D-Mode-Maintainers/Emacs-D-Mode/issues/23
[Fix #460] Extract column information from DMD
Merge branch 'dmd-columns'

* dmd-columns:
  [Fix #460] Extract column information from DMD
  Work around D Mode void-function error
Update Texinfo manual