Add examples using slices

Author: MasterDuke17

doc/Type/Hash.pod6

@@ -137,6 +137,13 @@ most idiomatic and unambiguous solution:
         lookup-user( %( name => "$person<firstName> $person<lastName>" ) );
     };
 
+=head2 Slices
+
+You can assign to multiple keys at the same time with a slice.
+
+    my %h; %h<a b c> = 2 xx *; %h.perl.say  # {:a(2), :b(2), :c(2)}
+    my %h; %h<a b c> = ^3;     %h.perl.say  # {:a(0), :b(1), :c(2)}
+
 =head2 Non-string keys
 
 By default keys in C<{ }> are forced to strings. To compose a hash with