Fourth patch update - Loading screens and Balancing

Added loading screen to the stand alone version as well as the webGL and added a text box to display what is being loaded.

added the pick Up magnet upgrade so that exp and gold orbs will be pulled towards you when you are in range.

hopefully fixed a bug where the upgraded throwing axe ability would not reset  at the end of each round and would cause the button to not show correctly after closing and reopening the game.

have done some balancing to the enemies and abilities to make them slightly tougher as the round goes on.