adding jasmine bindings for Asynchronous Support: runs, waits, waitsFor

Would you please merge these jasmine bindings based on this conversation?https://groups.google.com/d/msg/scala-js/N7W3yRfnnyc/NVQCbBu3SIoJ

It works as expected. Tested on PhantomJS where it is better to use it with default `autoExit=true`, because the test exits after the last runs() method which tests results that where collected asynchronously.
https://github.com/pivotal/jasmine/wiki/Asynchronous-specs#waitstimeout