the small fix for the game

The first small change is the UI, now when the reaches Level 4 the boss HP will show up on the top right of the Screen but' when not at Level 4 it will be invisible to the Player.

Next to show is the portal sprite for Level 3.

The last fix is the enemy hit box, when two enemy are right next to each other and when Mario jumps on them both hit box will damage Mario.