[Framework] Add bootstrapper

Add an application bootstrapper, responsible for
handling the Angular bootstrapping phase of
framework layer initialization. WTD-518.

platform/framework/src/FrameworkInitializer.js

@@ -45,7 +45,7 @@ define(
                     return loader.loadBundles(bundleList)
                         .then(resolver.resolveBundles)
                         .then(registrar.registerExtensions)
-                        .then(bootstrapper.bootstrapApplication);
+                        .then(bootstrapper.bootstrap);
 
                 }