Deprecate "common"?

[fernandojsg]

Right now we could do things like:

mappings: {
  task1 {
    common: {
      trackpaddown: 'teleport'
    },
    'windows-motion-controls': {
       ...
    }
  },

And it willl be applied to any device (if we don't override the trackpaddown event). I created it as I believe it was useful to avoid rewriting the same for each controller, although if we're going to focus on a json generated by a config UI that's not really a problem, or even if you need to create it by hand, is just one time and forget.

The other reason I thought it could be useful was in these cases where you don't have a mapping defined for a new device, so "hopefully" some of the mappings could still work and you'll see some interaction. But this assumption is quite poor because we can't just expect that new devices will have a trackpad or a trigger.

So my vote would be to remove it and to show a warning if a new device is detected but no mapping is defined and just force people to define a new mapping for it.