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/payloads/proposal_substructure.h

@@ -24,6 +24,8 @@
 #ifndef PROPOSAL_SUBSTRUCTURE_H_
 #define PROPOSAL_SUBSTRUCTURE_H_
 
+typedef struct proposal_substructure_t proposal_substructure_t;
+
 #include <types.h>
 #include <encoding/payloads/payload.h>
 #include <encoding/payloads/transform_substructure.h>
@@ -38,9 +40,6 @@
  */
 #define PROPOSAL_SUBSTRUCTURE_HEADER_LENGTH 8
 
-
-typedef struct proposal_substructure_t proposal_substructure_t;
-
 /**
  * @brief Class representing an IKEv2-PROPOSAL SUBSTRUCTURE.
  *