Set up a basic animation system

-Added:
  -Animation.cs
  -AnimFrame.cs
-Got basic animations working:
  -Specify animation frames from a spritesheet and pass them into the constructor
Completed basic functionality of Animation system

-Added:
  -An example of a unique animation for each of the 4 cardinal directions in Character.cs
  -Pause, Resume, Stop, and Play methods in Animation.cs for more control over animations
    -The Character class makes use of this by only playing the animation when the character is moving and stopping it when the character stops
Refined HUD System to Scale to Screen Resolution

-Added Gun test graphic and Clip Ammo + Total Ammo TextBlocks
-Added ClipSize and ReloadTime variables to the Gun.cs class
Merge branch 'FinishingBasicHUD' into AnimationSystem

Conflicts:
	Top Down Shooter/Top Down Shooter/HUD.cs
Merge branch 'AnimationSystem'