Remove of MaxLib.WebServer.Api.*

The content in the namespace `MaxLib.WebServer.Api.*` provides similar functionality as in `MaxLib.WebServer.Builder.*`. For the sake of easier maintenance the less feature rich will be removed in favor of the other one.

Current schedule:
-  `MaxLib.WebServer.Api.*` will be deprecated in Version `4.0.0`
-  `MaxLib.WebServer.Api.*` will be removed in Version `5.0.0`
