Fix krb5_cc_move() issues

Move init/copy/destroy fallback sequence from fcc_move() to
krb5_cc_move().

Make sure all backends's move() method calls krb5_cc_destroy() on the
source on success (and only on success).

In text_cc make sure that we can find in the destination the cred
stored into the source.

lib/krb5/acache.c

@@ -992,8 +992,7 @@ acc_move(krb5_context context, krb5_ccache from, krb5_ccache to)
 
     error = (*ato->ccache->func->move)(afrom->ccache, ato->ccache);
 
-    acc_destroy(context, from);
-
+    krb5_cc_destroy(context, from);
     return translate_cc_error(context, error);
 }