Allow truncating without using any ellipsis

Depending on how bindings are displayed showing docstrings can result
in most lines being too long and adding ellipses to most lines can be
quite ugly and distracting.

which-key.el

@@ -142,13 +142,13 @@ the default is \" : \"."
 
 (defcustom which-key-ellipsis
   (if which-key-dont-use-unicode ".." "…")
-  "Ellipsis to use when truncating. Default is \"…\", unless
-`which-key-dont-use-unicode' is non nil, in which case
-the default is \"..\"."
+  "Ellipsis to use when truncating.
+Default is \"…\", unless `which-key-dont-use-unicode' is non nil,
+in which case the default is \"..\".  This can also be the empty
+string to truncate without using any ellipsis."
   :group 'which-key
   :type 'string)
 
-
 (defcustom which-key-prefix-prefix "+"
   "String to insert in front of prefix commands (i.e., commands
 that represent a sub-map). Default is \"+\"."
@@ -1604,10 +1604,13 @@ If KEY contains any \"special keys\" defined in
 		(function (let ((val (funcall max avl-width)))
 			    (if (floatp val) (truncate val) val))))))
     (if (and max (> (length desc) max))
-	(let* ((last-face (get-text-property (1- (length desc)) 'face desc))
-               (dots (which-key--propertize which-key-ellipsis
-					    'face last-face)))
-          (concat (substring desc 0 (- max (length dots))) dots))
+        (let ((dots (and (not (equal which-key-ellipsis ""))
+			 (which-key--propertize
+			  which-key-ellipsis 'face
+			  (get-text-property (1- (length desc)) 'face desc)))))
+	  (if dots
+              (concat (substring desc 0 (- max (length dots))) dots)
+	    (substring desc 0 max)))
       desc)))
 
 (defun which-key--highlight-face (description)