Code Revamp and New UI

Took some time to reorganize the code a bit.  It grew organically from the merger of the __name__ == '__main__' from three different modules and was super unwieldy. I cleaned up the game interface into a few simple objects and reduced the spaghetti code by 23%.

There's now a simple UI, too.  The banner across the top (five minutes in Inkscape) tracks you followers and distance to goal.  The button box on the right holds n buttons (n=4 for now) that will be used to invoke powers to knock back the advancing goo.  Right now you just click the good to shoot a hole in it (at the cost of one follower).  You can technically win (outrun the goo) and loose (run out of followers) but that's about it.

Next up: Add some obstacles and collision detection (with obstacles and goo).  Then maybe powerups and floating notifications.