Angular 2 question only:
Whats the best way to store global variables like authentication token or base url (environment settings) so that all classes can have access to them without loosing them on refresh?
So when I login I will give the user a auth token and normally store it in the $rootscope for angular 1.x.
Well to create really global scope data you should register your class\object\value during the app bootstrapping as dependency parameter to the bootstrap function
This will register your service
MyGlobalService (infact it can be a object or factory function or your own provider) at the root level. This dependency now can be injected into any component.
Unlike Angular1 there are multiple Injectors available for an Angular2 app, with one-to-one mapping between components and injectors. Each component has its own injector.
The Angular developer guide has some good example of such registrations. See the guide on Dependency Injection.
The other option has already been highlighted by @Yaniv.