feat(debug): replace DebugElement with new Debug DOM

Now, using `ng.probe(element)` in the browser console returns
a DebugElement when in dev mode.

`ComponentFixture#debugElement` also returns a new DebugElement.

Breaking Change:

This is a breaking change for unit tests. The API for the DebugElement
has changed. Now, there is a DebugElement or DebugNode for every node
in the DOM, not only nodes with an ElementRef. `componentViewChildren` is
removed, and `childNodes` is a list of ElementNodes corresponding to every
child in the DOM. `query` no longer takes a scope parameter, since
the entire rendered DOM is included in the `childNodes`.

Before:

```
componentFixture.debugElement.componentViewChildren[0];
```

After
```
// Depending on the DOM structure of your component, the
// index may have changed or the first component child
// may be a sub-child.
componentFixture.debugElement.children[0];
```

Before:

```
debugElement.query(By.css('div'), Scope.all());
```

After:

```
debugElement.query(By.css('div'));
```

Before:

```
componentFixture.debugElement.elementRef;
```

After:

```
componentFixture.elementRef;
```

modules/angular2/test/public_api_spec.ts

@@ -890,19 +890,40 @@ var NG_CORE = [
   'PLATFORM_PIPES:js',
   'DebugElement',
   'DebugElement.children',
+  'DebugElement.attributes',
+  'DebugElement.attributes=',
+  'DebugElement.properties',
+  'DebugElement.properties=',
+  'DebugElement.childNodes',
+  'DebugElement.childNodes=',
+  'DebugElement.injector',
+  'DebugElement.injector=',
+  'DebugElement.listeners',
+  'DebugElement.listeners=',
+  'DebugElement.locals',
+  'DebugElement.locals=',
+  'DebugElement.name',
+  'DebugElement.name=',
+  'DebugElement.parent',
+  'DebugElement.parent=',
   'DebugElement.componentInstance',
-  'DebugElement.componentViewChildren',
-  'DebugElement.elementRef',
-  /*
-   Abstract methods
-  'DebugElement.getDirectiveInstance()',
+  'DebugElement.componentInstance=',
   'DebugElement.getLocal()',
-  'DebugElement.hasDirective()',
+  'DebugElement.providerTokens',
+  'DebugElement.providerTokens=',
   'DebugElement.inject()',
-  */
+  'DebugElement.nativeNode',
+  'DebugElement.nativeNode=',
   'DebugElement.nativeElement',
+  'DebugElement.nativeElement=',
   'DebugElement.query()',
   'DebugElement.queryAll()',
+  'DebugElement.queryAllNodes()',
+  'DebugElement.triggerEventHandler()',
+  'DebugElement.setDebugInfo()',
+  'DebugElement.addChild()',
+  'DebugElement.removeChild()',
+  'DebugElement.insertChildrenAfter()',
   'Dependency#fromKey()',
   'Dependency',
   'Dependency.key',
@@ -1208,10 +1229,6 @@ var NG_CORE = [
   'ResolvedFactory.dependencies=',
   'ResolvedFactory.factory',
   'ResolvedFactory.factory=',
-  'Scope#all()',
-  'Scope#light()',
-  'Scope#view()',
-  'Scope',  // TODO(misko): rename?
   'Self',
   'SelfMetadata',
   'SkipSelf',
@@ -1354,7 +1371,6 @@ var NG_CORE = [
   'provide()',
   'createNgZone()',
   'forwardRef():js',
-  'inspectElement()',
   'platform():js',
   'resolveForwardRef():js',
   'PLATFORM_COMMON_PROVIDERS',
@@ -1600,8 +1616,8 @@ var NG_PLATFORM_BROWSER = [
   'By#directive():js',
   'By:js',
   'DOCUMENT',
-  'ELEMENT_PROBE_BINDINGS:js',
   'ELEMENT_PROBE_PROVIDERS:js',
+  'ELEMENT_PROBE_PROVIDERS_PROD_MODE:js',
   'Title.getTitle():js',
   'Title.setTitle():js',
   'Title:js',