Update runtime files

runtime/doc/cmdline.txt

@@ -534,8 +534,46 @@ after a command causes the rest of the line to be ignored.  This can be used
 to add comments.  Example: >
 	:set ai		"set 'autoindent' option
 It is not possible to add a comment to a shell command ":!cmd" or to the
-":map" command and a few others, because they see the '"' as part of their
-argument.  This is mentioned where the command is explained.
+":map" command and a few others (mainly commands that expect expressions)
+that see the '"' as part of their argument:
+
+    :argdo
+    :autocmd
+    :bufdo
+    :cexpr (and the like)
+    :call
+    :cdo (and the like)
+    :command
+    :cscope (and the like)
+    :debug
+    :display
+    :echo (and the like)
+    :elseif
+    :execute
+    :folddoopen
+    :folddoclosed
+    :for
+    :grep (and the like)
+    :help (and the like)
+    :if
+    :let
+    :make
+    :map (and the like including :abbrev commands)
+    :menu (and the like)
+    :mkspell
+    :normal
+    :ownsyntax
+    :popup
+    :promptfind (and the like)
+    :registers
+    :return
+    :sort
+    :syntax
+    :tabdo
+    :tearoff
+    :vimgrep (and the like)
+    :while
+    :windo
 
 							*:bar* *:\bar*
 '|' can be used to separate commands, so you can give multiple commands in one