eliminated legacy 'axioms';

--- a/src/Doc/Tutorial/Protocol/Public.thy	Thu Feb 28 14:22:14 2013 +0100
+++ b/src/Doc/Tutorial/Protocol/Public.thy	Thu Feb 28 14:24:21 2013 +0100
@@ -47,8 +47,8 @@
 any public key.
 *}
 
-axioms
-  inj_pubK:        "inj pubK"
+axiomatization where
+  inj_pubK:        "inj pubK" and
   priK_neq_pubK:   "priK A \<noteq> pubK B"
 (*<*)
 lemmas [iff] = inj_pubK [THEN inj_eq]