Tutorial hints and pause button

I decided to make a small release composed of two problems mentioned by close friends.

First are some tutorial hints.

My friends were having some trouble understanding some key aspects of the game, even after I've explained them verbally, so I figured that newcomers will definitely encounter the same issues.

So, I added tutorial hints that trigger when some elements enter the field, explaining the basic mechanics.

Second, I added a pause menu and button, letting you restart the session or exit the game,

Since the game is full screen, I noticed it's a bit problematic for players with virtual soft keys (the back / home keys) to figure out how to exit the game so a new button in the top right corner was added, moving the hit-point hearts to the center.