WIP: update `Design in Interface Builder` in readme
WIP: update `Design in Interface Builder` in readme

seanwoodward/IBAnimatable,alexiosdev/IBAnimatable,JakeLin/IBAnimatable,IBAnimatable/IBAnimatable,seanwoodward/IBAnimatable,IBAnimatable/IBAnimatable,alexiosdev/IBAnimatable,JakeLin/IBAnimatable,IBAnimatable/IBAnimatable