Updating swipe up on home animations

> Scaling down home activity on swipe-up from home and spring back to place on cancel
> Fading out recents on swipe-up to home, so ensure that adjecent tiles also dissapear
> Instead of controlling alpha, controlling full transform for base and home task. This allows adding custom animation for home task on swipe up.
> Removing alpha hanging for fallback activity in baseSwipeHandler. Instead controlling full transform for home activity
> Adding feature flag to use QuickstepLauncher as 3P Launcher to make development easier.

Bug: 156398988
Change-Id: I69cc59f2c9c95d15df6926ba635e7d6c251dceb6