Transform dasherized properties to camelized in {{view}}.

After discussing the deprecations in https://github.com/emberjs/ember.js/pull/5388 with @mixonic, I believe that we actually need to allow consistent usage of dasherized property names from within Handlebars templates.

Dasherized properties are preferred for usage in HTML (and Handlebars).  This change allows the following:

```handlebars
{{some-component foo-bar="yeah"}}

{{! The component will have this.fooBar as "yeah" from above }}
```

This paves the way for a much more normal looking HTMLBars world:

```html
<some-component foo-bar="yeah" />

<!-- The component will have this.fooBar as "yeah" from above -->
```

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Once this is merged I will work on deprecating camelized usage in templates.  I have the deprecation ready, but will need to update a number of test templates to use the newly available dasherized versions.

The goal is a single clear rule: Use dasherized properties in templates/HTML, and camelized properties in JavaScript.