refactor(common): unify export structure

modules/@angular/common/src/location/index.ts

@@ -0,0 +1,13 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+export * from './platform_location';
+export * from './location_strategy';
+export * from './hash_location_strategy';
+export * from './path_location_strategy';
+export * from './location';