Expand the example with an Http dependant service

[SierraNL]

There seems to be a total lack of (working) examples on the internet on how to test a service which depends on Http. Since I guess 90% of the services depend on it, it would be a bit more of a real world example.

It would be awesome if it could be added to this repository, and the article on the website.

[Elecash]

I'm want to make a "Part 2" of the article with updated examples and some advanced topics about testing.

Not sure when I can have it finished, because I'm pretty busy, but I will write one eventually.