WebClient like API using HttpClient

# WebClient like API for HttpClient

As `WebClient` is an obsolete API (as far as I got told) and has some problems ([i.e. automatic redirecting](https://stackoverflow.com/questions/63327319/webclient-is-not-following-redirects-in-net-core-3-1)) it would be nice to have a similar replacement API using the HttpClient

# Problem

So, a few people have told me, that the `WebClient` API is marked as obsolete and the `HttpClient` should be used instead. The problem is that creating an asynchronous download with progress reports, and other very helpful stuff, is very easy with `WebClient`, but some messy code with `HttpClient`.

For this reason, most people will use the `WebClient` API and encounter the same problems over and over again.

# Solution

There are two possible solutions:
- Fix the `WebClient` API
- Implement a similar API with similar functionalities but based on the `HttpClient`