3.0.0

• Now requires PHP 5.5!
• Promise::all() is moved to Promise\all().
• Aside from the Promise\all() function, there's now also Promise\race().
• Promise\reject() and Promise\resolve() have also been added.
• Now 100% compatible with the Ecmascript 6 Promise.

Also contains all the changes from the previous alpha:

• #26: Added an event loop implementation. Also knows as the Reactor Pattern.
• Renamed Promise::error to Promise::otherwise to be consistent with
  ReactPHP and Guzzle. The error method is kept for BC but will be removed
  in a future version.
• #27: Support for Promise-based coroutines via the Sabre\Event\coroutine
  function.
• BC Break: Promises now use the EventLoop to run "then"-events in a separate
  execution context. In practise that means you need to run the event loop to
  wait for any then/otherwise callbacks to trigger.
• Promises now have a wait() method. Allowing you to make a promise
  synchronous and simply wait for a result (or exception) to happen.