Switch some level data around to test game logic
Added a new block pool that tells the game what new blocks to add. This makes it easier to replicate the same condition and makes the game more predictable. It also opens up new options for making the game harder (not dropping certain colors) or easier (dropping more of a certain color). Had to change the order of addReplaceBlocks so that it uses the sorted blocks so it always adds the correct new blocks.

New section added to level data files.
New generateLevel function with two new levels. Sea of Blue shows how to use the blockPool to create different game types (more blue blocks, higher target scores)
Cleaned up some of the resources and put interfaces into an atlas.