Created originally on Bitbucket by marky1991 (Mark Young)
Was already merged in Bitbucket before import, marked as merged by the import user
- Fix final two failing tests.
- Add support to create new tee objects from existing tee objects by passing arbitrary iterables.
- Fixed the scenario where you pickle and unpickle an empty iterator. (Make it raise StopIteration instead of a TypeError)
- Add pickleability of tee objects