Level Editor Added!

With this updated I've made a lot of changes / improvements since the jam ended.  I changed how images load, but as a result, now requires a 'data' folder with all my assets outside of the jar file.  I also need this because I added a level editor!  And this level editor requires me to output xml files of level data which are then loaded into the game when it's started.  This allows me to much more easily build a level instead of the silly primitive way I was doing it with certain colored pixels on the main gameboard representing the location of a certain entity.  Unfortunately the game never worked on the Winnitron arcade cabinet.  Don't ask me why...it works fine outside of Winnitron.

Also some other minor improvements:

- Fixed how the camera would scroll into blackness (still not working right once it zooms out though)

- Added zooming out when the blackhole scales up

- Added entity loading through xml

- Added dynamic image loading, so any png under the data folder will load into the game.

With all these changes, it should be much easier for anybody to mod the game by simply updating a few xml files and putting in their own png art assets and using the level editor to put things where-ever.