Add basic environment information to feedback

[ueman]

Users feedback should be enriched with basic environment information.

For Dart:IO this can be done with Platform. For Dart:HTML this can be done with the navigator.

[rohitbhoite]

Do we need to return Platform.environment in UserFeedback object?

[ueman]

I'm not sure what you're asking. There's no need to do this, but it's a welcomed change. As of now, if you want it, you have to do it yourself.