Fix argument order for Objects calls
Cache Signal proxy
Rename Signal.tuple to Signal.zip

- add Signal.prototype.zip
Add Signal.map

- returns an object whose values are signals
Rename Future to Deferred

- the terms Future and Promise are used in other languages and the use of Future as the producer is the opposite of these, so sticking to the JavaScript view of the Promise as the producer
- Deferred is also common in JavaScript land
Update Ajax specs
Tweaking spec resources

- renamed specrunner.html to index.html for less typing
Removed unused variable in promise module