Network Plugin, Using generic type in MvxRestClient for MvxRestResponse

I just wrote some custom classes inheriting from MvxStreamRestResponse and I was pretty confused that I was not able to pass them as callback argument into `MvxRestClients' MakeRequest()`.

Long story short: I implemented the `MakeRequest()` method in a way that it will handle any custom implementation inheriting MvxRestResponse.

Also the line indention was pretty awkward, so I normalized and code formatted the whole `MvxRestClient' class file.