babeld: Initial import, for Babel routing protocol.

* Initial import of the Babel routing protocol, ported to Quagga.
* LICENCE: Update the original LICENCE file to include all known potentially
  applicable copyright claims.  Ask that any future contributors to babeld/
  grant MIT/X11 licence to their work.
* *.{c,h}: Add GPL headers, in according with the SFLC guidance on
  dealing with potentially mixed GPL/other licensed work, at:

  https://www.softwarefreedom.org/resources/2007/gpl-non-gpl-collaboration.html
diff --git a/lib/memory.c b/lib/memory.c
index 4090fd9..63ec6b5 100644
--- a/lib/memory.c
+++ b/lib/memory.c
@@ -466,6 +466,17 @@
   return CMD_SUCCESS;
 }
 
+DEFUN (show_memory_babel,
+       show_memory_babel_cmd,
+       "show memory babel",
+       SHOW_STR
+       "Memory statistics\n"
+       "Babel memory\n")
+{
+  show_memory_vty (vty, memory_list_babel);
+  return CMD_SUCCESS;
+}
+
 DEFUN (show_memory_bgp,
        show_memory_bgp_cmd,
        "show memory bgp",