Created Gun & Projectile System

-Associated a gun with a player
-Associated a projectile with a gun
-Created a MachineGun type for testing
-Created a Projectile1 type for testing
-Created basic graphics for the test gun and projectile
-Created a helper class, Helper.cs
-Centered the gun on the player's sprite, and centered the projectile on the gun's sprite
Added Collideable interface and completed more of the Hitbox and Hurtbox classes

Added:
  -Debug.cs for debugging
  -Collideable.cs as an interface for objects that block others via movement
  -ScalableBox.png for allowing for easy showing of boxes such as Hitbox and Hurtboxes for debugging purposes
Merge branch 'MovementCollisions' into GunSystem

Conflicts:
	Top Down Shooter/Top Down Shooter/Top Down Shooter.csproj
Merge branch 'GunSystem'