Added no-autodie-twice.t test

It reproduces the issue Dual-Life#80 :

More: Scoping issue with "no autodie" and the "system" sub
Dual-Life#80

Author: pmorch

t/no-autodie-twice.t

@@ -0,0 +1,13 @@
+#!/usr/bin/perl
+use Test::More;
+
+{ no autodie; }
+{ no autodie; }
+
+eval {
+    system("echo something");
+};
+
+ok(! $@, 'system worked')
+    or diag explain $@;
+done_testing();