connectionmanager: fix certificate pinning and factory lifecycle

1. findCertificate must pin certificate in certificate store
in order to re-use it afterwards.
2. Pass IceTransportFactory in config, else it will be destroyed
before all ICE Transport are closed.

Change-Id: I86398df9e0f26309719ef46989b422cc4b1b7732
diff --git a/include/connectionmanager.h b/include/connectionmanager.h
index e6ad37b..e459eb3 100644
--- a/include/connectionmanager.h
+++ b/include/connectionmanager.h
@@ -18,6 +18,7 @@
 
 #include "ice_options.h"
 #include "multiplexed_socket.h"
+#include "ice_transport_factory.h"
 #include "turn_cache.h"
 
 #include <opendht/dhtrunner.h>
@@ -248,6 +249,8 @@
 
     tls::CertificateStore* certStore;
 
+    dhtnet::IceTransportFactory* factory;
+
     /**
      * UPnP IGD controller and the mutex to access it
      */