Custom JSON Transforms : Update sample code

The 'registerTransform' method has been removed, and there is a new
way to register a custom JSON transform.
adding BrandingBrand to users
Update the transform example to match the latest changes.
using public api for queries, instead of private store.findQuery
Merge pull request #844 from brandingbrand/master

Ember User Logo Contact: Branding Brand
Explain 'App' and how it relates to Ember and fix line length
Merge pull request #995 from ecryan/master

Explain how 'App' relates to an Ember application because this was not referenced prior to its usage. So seeing App.ApplicationRoute or App.ApplicationController may make sense to someone that may not know what that is exactly means.
Remove redundant word.
Merge pull request #996 from ugisozols/remove_redundant_word

Remove redundant word.
Improve observers guide
Merge pull request #997 from alexspeller/improve-observer-guide

Improve observers guide
Merge pull request #993 from sly7-7/ember-data-queries

Refer to public api for queries instead of private store.findQuery
Merge pull request #760 from jagthedrummer/jeremy/models-transforms

Custom JSON Transforms : Update sample code
Use `action` instead of `event`.

Resolves #919.
Update links.md to display Handlebars code snippet correctly on website

Adds an extra line to allow website to display Handlebars code snippet correctly.
Wrapped body with has a x-handlebars template.

The TodoMVC tutorial wasn't working after step "displaying-model-data" because the http://emberjs.com/guides/getting-started/creating-a-static-mockup/ step didn't include this from the start. It is in the Live Preview but this might confuse beginners.
Merge pull request #999 from bluk/patch-1

Update links.md to display Handlebars code snippet correctly on website
Merge pull request #1000 from hbarroso/patch-1

Wrapped body with a x-handlebars template.
Merge pull request #998 from rjackson/use_action_in_router_docs

Use `action` instead of `event`.