Resolve "Implement projectile logic"

frontend/android/build.gradle

frontend/build.gradle

frontend/core/build.gradle

frontend/core/src/com/game/tankwars/TankWarsGame.java

frontend/core/src/com/game/tankwars/model/Box2dWorld.java

frontend/core/src/com/game/tankwars/model/Bullet.java

frontend/core/src/com/game/tankwars/model/Tank.java

frontend/core/src/com/game/tankwars/view/GameScreen.java

frontend/desktop/build.gradle