jhatwich/layer comps+size

To use this feature add a layer comp and name it something like "overview.png" or "200% overview.png"
This would be a little easier to read if you moved this statement above the `boundsAcquiredDeferredPromise.then` statement. I'd also rename that variable to just `boundsAcquiredPromise` since in some code paths it has nothing to do with `boundsAcquiredDeferred`. Ideally that later variable would only be initialized if necessary.