[vty] Add support for a 'restricted mode' with anonymous vty connections

	* lib/command.h: Add a RESTRICTED_NODE, intended for use with
	  anonymous, 'no login' vtys, to provide a subset of 'view' mode
	  commands.
	* lib/command.c: Add RESTRICTED_NODE bits, nothing special, just
	  following VIEW_NODE.
	* lib/vty.c: (vty_auth) enable authentication should fall back to
	  restricted/view node as appropriate.
	  (vty_create) init vty's to restricted/view node as appropriate,
	  for the 'no login' case.
	  (vty_{no_,}restricted_mode_cmd) config commands to enable
	  'anonymous restricted' in vty configuration.
	  (vty_config_write) 'anonymous restricted' config.
	  (vty_init) Install some commands to restricted mode, and the
	  'anonymous restricted' config commands into VTY_NODE.
	* bgpd/*.c: Install some of the safe(r) BGP commands into
	  'restricted mode', i.e. lookup commands of non-sensitive data.
	  Useful with looking-glass route-servers.
diff --git a/lib/memory.c b/lib/memory.c
index 28b3d89..f5d0cba 100644
--- a/lib/memory.c
+++ b/lib/memory.c
@@ -444,6 +444,16 @@
 void
 memory_init (void)
 {
+  install_element (RESTRICTED_NODE, &show_memory_cmd);
+  install_element (RESTRICTED_NODE, &show_memory_all_cmd);
+  install_element (RESTRICTED_NODE, &show_memory_lib_cmd);
+  install_element (RESTRICTED_NODE, &show_memory_rip_cmd);
+  install_element (RESTRICTED_NODE, &show_memory_ripng_cmd);
+  install_element (RESTRICTED_NODE, &show_memory_bgp_cmd);
+  install_element (RESTRICTED_NODE, &show_memory_ospf_cmd);
+  install_element (RESTRICTED_NODE, &show_memory_ospf6_cmd);
+  install_element (RESTRICTED_NODE, &show_memory_isis_cmd);
+
   install_element (VIEW_NODE, &show_memory_cmd);
   install_element (VIEW_NODE, &show_memory_all_cmd);
   install_element (VIEW_NODE, &show_memory_lib_cmd);