Compile fix.

lib/Connection.cpp

@@ -19,6 +19,7 @@
 #include "../hch/CArtHandler.h"
 #include "../hch/CHeroHandler.h"
 #include "../hch/CTownHandler.h"
+#include "../hch/CCampaignHandler.h"
 
 
 /*
@@ -377,4 +378,4 @@ void CSerializer::addStdVecItems(CGameState *gs, LibClasses *lib)
 	registerVectoredType(&lib->arth->artifacts, &CArtifact::id);
 	registerVectoredType(&lib->heroh->heroes, &CHero::ID);
 	smartVectorMembersSerialization = true;
-}
+}