(Standard Keymaps): Add xref for minibuffer maps.

Add apropos-mode-map, custom-mode-map, esc-map, global-map,
grep-mode-map, help-map, help-mode-map, kmacro-map, and tool-bar-map.

lispref/maps.texi

@@ -12,11 +12,17 @@ Some of these exist when Emacs is first started, others are
 loaded only when their respective mode is used.  This is not
 an exhaustive list.
 
+Several keymaps are used in the minibuffer.  @xref{Completion Commands}.
+
 Almost all of these maps are used as local maps.  Indeed, of the modes
 that presently exist, only Vip mode and Terminal mode ever change the
 global keymap.
 
 @table @code
+@item apropos-mode-map
+@vindex apropos-mode-map
+A sparse keymap for @code{apropos} buffers.
+
 @item Buffer-menu-mode-map
 @vindex Buffer-menu-mode-map
 A full keymap used by Buffer Menu mode.
@@ -38,6 +44,9 @@ A sparse keymap for subcommands of the prefix @kbd{C-x 5}.
 @item ctl-x-map
 A full keymap for @kbd{C-x} commands.
 
+@item custom-mode-map
+A full keymap for Custom mode.
+
 @item debugger-mode-map
 @vindex debugger-mode-map
 A full keymap used by Debugger mode.
@@ -66,6 +75,10 @@ A full keymap used by Electric Command History mode.
 @vindex emacs-lisp-mode-map
 A sparse keymap used by Emacs Lisp mode.
 
+@item esc-map
+@vindex esc-map
+A full keymap for @kbd{ESC} (or @kbd{Meta}) commands.
+
 @item facemenu-menu
 @vindex facemenu-menu
 The sparse keymap that displays the Text Properties menu.
@@ -109,6 +122,21 @@ If there are none, then it contains an empty sparse keymap.
 The sparse keymap for Fundamental mode.@*
 It is empty and should not be changed.
 
+@item global-map
+The full keymap containing default global key bindings.@*
+Modes should not modify the Global map.
+
+@item grep-mode-map
+@vindex grep-mode-map
+The keymap for @code{grep-mode} buffers.
+
+@item help-map
+The sparse keymap for the keys that follow the help character @kbd{C-h}.
+
+@item help-mode-map
+@vindex help-mode-map
+The sparse keymap for Help mode.
+
 @item Helper-help-map
 @vindex Helper-help-map
 A full keymap used by the help utility package.@*
@@ -132,6 +160,11 @@ search.
 A keymap for translating keys.  This one overrides ordinary key
 bindings, unlike @code{function-key-map}.  @xref{Translating Input}.
 
+@item kmacro-map
+@vindex kmacro-map
+A sparse keymap for keys that follows the @kbd{C-x C-k} prefix
+search.
+
 @item lisp-interaction-mode-map
 @vindex lisp-interaction-mode-map
 A sparse keymap used by Lisp Interaction mode.
@@ -184,6 +217,9 @@ time.
 @vindex text-mode-map
 A sparse keymap used by Text mode.
 
+@item tool-bar-map
+The keymap defining the contents of the tool bar.
+
 @item view-mode-map
 @vindex view-mode-map
 A full keymap used by View mode.