Add libtool support.

libzebra and libospfapiclient are now built shared, and linked shared
with the daemons.  This reduces the memory needed when running
multiple daemons; each daemon is at least 150k smaller.  Static
libraries are still built, and libtool should use them on platforms
which don't have shared libaries.  As with autoconf, the user of a
distribution does not need libtool; one just needs that to build from
CVS.

libospf.a is still a non-shared library, and still installed, not
because that makese sense, but because I don't understand why it is
the way it is now.

Note that the tree was tagged 'libtool-before' just before this commit.
diff --git a/ospfclient/Makefile.am b/ospfclient/Makefile.am
index 035ee90..6c5a8cd 100644
--- a/ospfclient/Makefile.am
+++ b/ospfclient/Makefile.am
@@ -2,10 +2,10 @@
 
 INCLUDES = -I../lib -I../
 
-lib_LIBRARIES = libospfapiclient.a
+lib_LTLIBRARIES = libospfapiclient.la
 sbin_PROGRAMS = ospfclient
 
-libospfapiclient_a_SOURCES = \
+libospfapiclient_la_SOURCES = \
 	ospf_apiclient.c
 
 ospfapiheaderdir = $(pkgincludedir)/ospfapi
@@ -14,8 +14,9 @@
 	ospf_apiclient.h
 
 ospfclient_SOURCES = \
-	ospfclient.c $(libospfapiclient_a_SOURCES)
+	ospfclient.c
 
-ospfclient_LDADD = ../ospfd/libospf.a ../lib/libzebra.a @LIBCAP@
+ospfclient_LDADD = libospfapiclient.la \
+	-L../ospfd -lospf -L../lib -lzebra @LIBCAP@