Switch to wget instead of curl

[jvanbaarsen]

Not every server has CURL installed. wget is always installed. Let's switch the installer to wget, so we are not forcing users to install unneeded dependencies on their server.

[michiels]

I'm not sure if this is correct, my experience is the other way around :p But lets target Ubuntu 16.04 for now. Or maybe add it as a dependency check when starting the script.

[jvanbaarsen]

@michiels It's not about starting the script. It's even with the command we show on intercity.io. When I install a clean ubuntu virtual box, I do have access to wget, but not curl. This was the reason I assumed it was more widely available. We can also just assume that people know how to install curl of it is not present.