Transition Behavior

new transitionBehavior prop on <After />

transitionBehavior: instant | blocked

the default for value for transitionBehavior prop is blocked (we can also change the default to instant but it's going to be a breaking change)

blocked behavior (default):

navigation event occurs -> wait until getInitailProps get finished -> render the next page with injected props (I mean results of the getInitailProps)

instant behavior:
navigation event occurs -> call getInitailProps -> render the next page -> re-render component when getInitailProps is finished with injected props