Google Play services is dropping support for KitKat. We follow them since lack of updates implies the Dynamic Security Provider also doesn't receive updates, which is a concern for security. And if the market share of an Android version becomes low enough that they can drop support, it is generally a good signal that we can.

Not much changes, except turning off some tests. This is mostly updating our minimum version in our package and the README.

CC @markb74 @jdcormie