[Issue Fixed] When onBackPressed() from NewActivity, the MainActivity…

[Grindewald1900]

… is covered by the scaled Transition Button

[Grindewald1900]

Hi, I love this custom button. However, I found it weird when the back button is pressed from new activity, the button occupies the whole screen. So I added a new method resetAnimation() to TransitionButton, and exposed it to other activities, to resize the button and clear the animation.