Proxy does not comply with JSON

[MeKHell]

Issue:
The "/evoting/adminlist" endpoint of the API exposed by the proxy returns something which does not comply with JSON standards:
It is neither an array nor an object.
In order to be easily parsed by JSON libraries, it would be way better if it was complying with these standards

Fix:

I think creating a trivial object with a single key-value pair as it is done on the "/evoting/forms" endpoint is the best idea.

[MeKHell]

This is required to correctly solve #175.