Changes for version 0.02
- add several predicate methods to help when interrogating status, this resolves RT #81278.
- thanks to Toby Inkster for this
- fixed error chaining so that the result of an error in one step of the chain will be passed onto the next step as well, this resolves RT #81358.
- thanks to TOSHIOITO for this
- made error callbacks optional and ensured that the errors will bubble to the next promise in the chain, this resolves RT #81356.
- thanks again to TOSHIOITO for this