Catch up to changes in Xcode 6 beta 3.

 - change the array type notation from "Type[]" to "[Type]".
 - in HNTask#all() and HNTask#allSettled(), 'results' is now variable (not constant) because of changes in array semantics.
 - avoiding compiler crash (it makes compiler crash...? that passing array variable to a method which takes a parameter of type 'Any')