Improved the UI Overall - More Consistency and a Retro Feel

-Created a fade-in animation that displays ʺLevel #ʺ in the center of the screen when a new level begins
-Made the game font and the game's entire UI more retro-styled by using the Consolas font everywhere
-Created a base XAML style for Buttons, and used it on every button to improve UI consistency
-Made touch input work for killing enemies
-Used the Shop Background image on the Level End screen
Made the invincibility effect look much nicer

-Added GetDrawDepth in LevelObject.cs, which gets the depth based on the Y position of the object
  -This allows objects with lower Y positions to be drawn above objects with higher Y positions
-Fixed drawing position issues when an object is rotated (in AnimFrame). As a result, spears now draw properly while falling
-Modified several classes to call GetDrawDepth as the depth value for their Animations/AnimFrames instead of arbitrarily high depth values that would have conflicted if the objects overlapped
Continued Improving the Overall UI

-Displayed the player's Health and Gold in the Shop
-The player's Health and Gold is updated on the HUD when a new level begins
-Made the Level Start animation pause if the game is paused and resume when the game is resumed. It ignored pausing before
-Put the code for ending a level into void EndLevel(), and called that method instead
-Added the following methods for updating the player's HP and Gold in the shop: void UpdateGoldAmountInShop() and void UpdateHealthInShop()
-Fixed the appearance of Buttons both on the HUD and everywhere else in the game
Merge remote-tracking branch 'origin/GeneralUIImprovements2' into NicerInvincibility

Conflicts:
	Defend Your Castle/Defend Your Castle/Level.cs
Fixed some formatting issues in the merge conflict
Merge branch 'NicerInvincibility'