refactor(core): introduce ComponentFactory.

Each compile template now exposes a `<CompName>NgFactory` variable
with an instance of a `ComponentFactory`.
Calling `ComponentFactory.create` returns a `ComponentRef` that can
be used directly.

BREAKING CHANGE:
- `Compiler` is renamed to `ComponentResolver`,
  `Compiler.compileInHost` has been renamed to `ComponentResolver.resolveComponent`.
- `ComponentRef.dispose` is renamed to `ComponentRef.destroy`
- `ViewContainerRef.createHostView` is renamed to `ViewContainerRef.createComponent`
- `ComponentFixture_` has been removed, the class `ComponentFixture`
  can now be created directly as it is no more using private APIs.

modules/benchmarks/src/largetable/largetable_benchmark.ts

@@ -113,7 +113,7 @@ export function main() {
     bootstrap(AppComponent, _createBindings())
         .then((ref) => {
           var injector = ref.injector;
-          app = ref.hostComponent;
+          app = ref.instance;
           appRef = injector.get(ApplicationRef);
           bindAction('#ng2DestroyDom', ng2DestroyDom);
           bindAction('#ng2CreateDom', ng2CreateDom);