Can't change the Relay URL after settings.json has been saved within appPath

[michaelbayday]

Can't change the Relay URL after settings.json has been saved within appPath.

Workflow:

1. I had setup my Zen client to use the public relay
2. Reinitialized application and tried inputting my server running zen relay on the initial screen where you input uuid and relay url.
3. Client would not connect.
4. I had to delete settings.json (differnet per OS)