MLEHMANN ignores Perl newer than 5.22, disable feature signatures

Index: Serialiser.pm
--- Serialiser.pm.orig
+++ Serialiser.pm
@@ -17,6 +17,7 @@ different implementations so they become interoperable
 
 package Types::Serialiser;
 
+no feature 'signatures';
 use common::sense; # required to suppress annoying warnings
 
 our $VERSION = '1.01';
