Remove window-max-characters-per-line

Remove window-max-characters-per-line

* doc/lispref/windows.texi (Window Sizes):
* doc/lispref/display.texi (Size of Displayed Text): Remove
documentation.
* lisp/fringe.el (fringe-mode): Point to the right function.

* lisp/window.el (window-char-pixel-width)
(window-char-pixel-height, window-max-characters-per-line): Remove
functions -- this was already added as window-max-chars-per-line.

* src/window.c (Fwindow_body_width): Adjust doc string.