WeakMap & WeakSet support

[jafl]

My tests indicate that Array.from() does not work on WeakMap and WeakSet, so I don't think these should be removed from objectSorter.js

[SkeLLLa]

Yep, you're right. It was there due to some historical reasons :). That time there was a discussion about adding some methods from set/map to weak set/maps. So that was made for "future" :).

I've removed weak* from code and readme. See 1.4.2 version.

Thanks.