Reject Until Errors.

Otherwise, if you have a catch block tied to this promise, it will
never get called.
No longer attempting to reject a resolved promise within [PMKPromise when:]. Fixes #97
Merge pull request #102 from codecaffeine/reject-until-errors

Reject ‘Until’ Errors
Fix tests
Merge oztune-master
Tests for until

Tag 0.9.21