JWT Authentication with ASP.NET Core 2 Web API, Angular 5, .NET Core Identity and Facebook Login

This is an updated version of a post I did last May on the topic of jwt auth with Angular 2+ and ASP.NET Core Web Api. That post was based on ASP.NET Core 1.x so it's a little dated and not as relevant now since everyone is hacking on .NET Core 2.0 which brought changes to both the Identity membership system and jwt implementation.