Settings page to configure Displays

[kasimos]

A settings page containing most of the currently hardcoded parameters of the config.js would be nice. Having the ability to simply add or remove a display on runtime is something that comes in handy as it doesn’t require a restart of the service.
Those settings could also be stored as part of the data folder to allow an easy migration from one deployment to another one.
I’m currently already working on this and will link this ticket accordingly.