Restructure deployment methods

[JannisBush]

The localServer deployment currently gives this error.
Probably we only have to add another or here https://github.com/babe-project/babe-project/blob/master/src/babe-views.js#L1491

[x-ji]

Actually I wonder if this deployment method is still relevant. Can we just write directLink and specify the server URL as http://localhost:4000?

[JannisBush]

Yeah I also thought about that and just using directLink with http://localhost:4000, as you have suggested, should work.

I also thought about getting rid of the deployment methods for MTurk and Prolific, because they could also be used in the debug or directLink environments. We only need one additional parameter, e.g. externalDeployment, which is empty by default and you can enter MTurk, MTurkSandbox or an ProlificURL there.