Clarify Any.list

Even though Any.list returns a List, clarify that subclasses can return
any Positional for this method.

Author: zoffixznet

doc/Type/Any.pod6

@@ -84,8 +84,8 @@ L<none>-L<Junction> from it.
 
 Defined as:
 
-    multi method list(Any:U: -->List)
-    multi method list(Any:D \SELF: -->List)
+    multi method list(Any:U: --> List)
+    multi method list(Any:D \SELF: --> List)
 
 
 Applies the infix L«C<,>|/routine/,»
@@ -95,6 +95,10 @@ and returns the resulting L<List>:
     say 42.list.^name;           # OUTPUT: «List␤»
     say 42.list.elems;           # OUTPUT: «1␤»
 
+Subclasses of C<Any> may choose to return any L<Positional> type
+from L«C<.list>|/routine/list>. Use L«C<.List>|/routine/List> to
+coerce specifically to L<List>.
+
 =head2 method push
 
 Defined as: