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/routemap.h b/lib/routemap.h
index 1402f5c..ba64553 100644
--- a/lib/routemap.h
+++ b/lib/routemap.h
@@ -43,6 +43,7 @@
 {
   RMAP_RIP,
   RMAP_RIPNG,
+  RMAP_BABEL,
   RMAP_OSPF,
   RMAP_OSPF6,
   RMAP_BGP,