First try at version 2.

Soooo. Consider this a work in progress, though this is as far as I've gotten with about a day's worth of work.

Animating blurRadius didn't yield as many benefits as I'd hoped. Part of the problem is that our blur kernel, which Accelerate takes in, accepts odd integers. So the scaling between various levels of blurring is not... smooth. It's _chunky_. Argh.

You can try working with blur radius and scale factor to get something to animate, but the results aren't pretty. I'm not really sure where to begin, for that matter, with animating scale factor because Core Animation custom parameters don't offer nearly the level of customization that I want.

Besides beating myself up over that, there's also now an option in the LFGlassLayer to offer custom frames, bounds, positioning (think like "center"), anchor points, and target layers, so that should resolve the LONG AWAITED PR #3.

That looks pretty good, and there's lots of helper code to help make that feature easy to use. I hope folks like it.