PromiseArray rejection handler only handles one rejected promise

[jparker-hbo]

Change afa323b fixed issue #135 so now this situation is no longer unhandled:

Promise.all([Promise.rejected("one")]).catch(...);

But if you do two or more, only the first one is handled:

Promise.all([Promise.rejected("one"), Promise.rejected("two")]).catch(...);

I'm not sure what the right behavior is, but maybe the first rejection should call the array's reject handler and then any other rejections are ignored?