Merge isisd into the Quagga's framework:
  - add privs support
  - use misc quagga's definitions
  - make it compile"able"
  - fix segfault cases related to hostname()
  - add debug isis xxx command

This patch has been approved by Paul Jakma.
diff --git a/Makefile.am b/Makefile.am
index 699c530..46cabb2 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,10 +1,11 @@
 ## Process this file with automake to produce Makefile.in.
 
 SUBDIRS = lib @ZEBRA@ @BGPD@ @RIPD@ @RIPNGD@ @OSPFD@ @OSPF6D@ \
-         @VTYSH@ @OSPFCLIENT@ doc
+         @ISISD@ @VTYSH@ @OSPFCLIENT@ doc
 
 DIST_SUBDIRS = lib zebra bgpd ripd ripngd ospfd ospf6d vtysh \
-	       ospfclient doc
+	       ospfclient doc \
+	       isisd
 
 EXTRA_DIST = aclocal.m4 SERVICES TODO REPORTING-BUGS vtysh/Makefile.in \
 	vtysh/Makefile.am update-autotools doc/mpls