Make field input focus and numpad visibility depend on how the field was clicked

[paulkaplan]

Right now we use user agent matching to find android/iOS and use that to determine (a) whether to show the numpad or not and (b) whether to focus the fields who have editors that use html inputs (in order to prevent the onscreen keyboard from appearing).

We should move to somehow detecting whether the field click came from a mouse or a touch, and use that information to show the number pad and prevent field focus.

/cc @picklesrus this is the issue we were discussing the best way to approach.