Add initial TKM integration test

A connection between the hosts moon and sun is set up. The host moon
uses the Trusted Key Manager (TKM) and is the initiator of the transport
connection. The authentication is based on X.509 certificates.

testing/tests/tkm/host2host-initiator/posttest.dat

@@ -0,0 +1,4 @@
+moon::DAEMON_NAME=charon-tkm ipsec stop
+moon::killall tkm_keymanager
+moon::rm -f /tmp/tkm.rpc.ike /tmp/tkm.rpc.ees /tmp/tkm.log
+sun::ipsec stop