Firebase 2.0.x

This pull request does the following:
* Updates bower.json to Firebase 2.0.x
* Changed name() to key()
* Added limitToFirst and limitToLast
* Added limit depreciated comment and message
* Added orderByChild
* Added orderByKey
* Added orderByPriority
* Added to firebase-element demo examples using Dinosaur Facts from Firebase
* Changed references to platform.js to webcomponents.js

I have signed the Google Contributor License Agreement

AgreementName | Name | Date Signed
------------ | ------------- | -------------
Google Individual CLA | Chuck Horton |	Nov 06, 2014 12:52 PST