Move away from Http and use Httpclient

[wesselvdv]

Move away from Http and use Httpclient. Allows us to use the Interceptor mechanic.

[agustinvinao]

I've created a pull request with a HttpClient implementation. #96

[hpawe01]

There was the switch to 4.0 a few days ago but this wasn't part of it. @agustinvinao are you planning to make a new pull request with only the HttpClient-Changes as suggested in the #96 (comment)?

And does this mean, this will not be added until 5.0?

[KariiO]

Any news on that?