Adds missing handlers calls

[alexbonhomme]

This implementations currently doesn't work, because onFulfilled and onRejected handlers aren't call during the final resolve. This patch just fix the missing calls according to the original post on SO. (http://stackoverflow.com/questions/23772801/basic-javascript-promise-implementation-attempt/23785244#23785244)

[ForbesLindesay]

They're currently added in the "Observing (via .done)" section, although that should probably be made more obvious. If you think we should include them from the start, make sure you add them to every occurrence of those functions. Another option might be to just add a // ... to indicate that there is more to add to the function later.

[alexbonhomme]

You're right, I didn't seen it at all. My mistake !

In my opinion, two things are missing :

• The complete code at the end
• A more segmented presentation of the code

I can do an other pull request with this if you want ?

[ForbesLindesay]

That would be great

[alexbonhomme]

Please have a look :-) #37
Sorry for the potential english mistakes, that's not my mother tongue.