fix(router): export navigation strategies

the replace, invoke lifecycle, and no_change strategies
needed to be exported so that they could be used

src/index.js

@@ -3,4 +3,5 @@ export {AppRouter} from './app-router';
 export {PipelineProvider} from './pipeline-provider';
 export {Redirect} from './navigation-commands';
 export {RouteLoader} from './route-loading';
-export {RouterConfiguration} from './router-configuration';
+export {RouterConfiguration} from './router-configuration';
+export {NO_CHANGE, INVOKE_LIFECYCLE, REPLACE} from './navigation-plan';