Add driver view v2 (with radio buttons)

[leolost2605]

As suggested this groups drivers by device. Since this required quite a few more steps where different cli outputs have to be parsed, compared, compared again and then double checked, this PR (or rather the settings-daemon side of it) should be tested thoroughly. I've tested with a nvidia card and there it works however I don't know how it will behave with two or more devices etc.

Probably needs some UI refinements :)

elementary/settings-daemon#141