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/vtysh/Makefile.am b/vtysh/Makefile.am
index fea0cb0..ebc5553 100644
--- a/vtysh/Makefile.am
+++ b/vtysh/Makefile.am
@@ -11,7 +11,7 @@
 nodist_vtysh_SOURCES = vtysh_cmd.c
 CLEANFILES = vtysh_cmd.c
 noinst_HEADERS = vtysh.h vtysh_user.h
-vtysh_LDADD = ../lib/libzebra.a @LIBCAP@
+vtysh_LDADD = -L../lib -lzebra @LIBCAP@
 
 examplesdir = $(exampledir)
 dist_examples_DATA = vtysh.conf.sample