moved typedefs to beginning of files to solve some include problems

splitted authenticator to have a separate implementation for each auth_method_t
using va_copy to clone va_lists, should fix proplems on AMD64
some other cleanups

src/charon/encoding/message.h

@@ -25,6 +25,8 @@
 #ifndef MESSAGE_H_
 #define MESSAGE_H_
 
+typedef struct message_t message_t;
+
 #include <types.h>
 #include <sa/ike_sa_id.h>
 #include <network/packet.h>
@@ -39,9 +41,6 @@
  */
 #define MESSAGE_PRINTF_SPEC 'M'
 
-
-typedef struct message_t message_t;
-
 /**
  * @brief This class is used to represent an IKEv2-Message.
  *