Change to Promises/A+ spec

- this is the de facto spec for Promises in JavaScript and will be more familiar to JS devs than a Scala derived Future/Promise API
- then() allows through handler behaviour the functionality offered through the Scala based API
Minor code cleanup
Update to Jasmine 2.0
Refactor ajax module to simplify API
Add implicit rejection of Promise in constructor

- if constructor callback throws an error, promise is implicitly
  rejected
Update build files for Jasmine 2.0
Change Promise.resolve to accept thenable

- returned promise will take state of thenable when completed
Remove Promise.rejected

- moved to api.promise