Can't connect to server with self-signed certificate.

[GitGregOT]

Hi. First of all, your app is great!
I have a self-signed Nextcloud server running the Subsonic API. When trying to connect to it with Audinaut, an error occurs: "Connection failure. A network error occured. Please check the server adress or try again later.". This happens with the "autentication method" toggled either way.
Other android app, Ampache, can connect to it and works with no problems, it has an "allow self-signed certificate" option. Maybe Audinaut can implement something similar?
Thanks!

[UnPossible-Me]

Same issue for me, it used to work just fine, but now it simply refuses to connect.

[IeP4nieF]

I think, that this is the same problem as described in: #100