Add Perl6 version

perl6/lib/Item.pm6

@@ -0,0 +1,11 @@
+use v6;
+
+class Item {
+    has Str $.name;
+    has Int $.sell_in is rw = 0;
+    has Int $.quality is rw = 0;
+
+    method Str {
+	"{$!name}, {$!sell_in}, {$!quality}"
+    }
+};