Changed use of get for hash lookup to implicit lookup using symbols
Altered tick function to add cache-click annotation to grid
Attempts to improve occupied block points
Added code for fallers and tests for some of the methods
Simplified fallers-block-below function
Added modifications and tests to support falling blocks
Added modifications and tests to support falling blocks
Fixed conflict
Added logging method
Added single var to hold step-rate
Fixed bug with swapping blocks and dissolving blocks
Fixed problem with disappear blocks
Fixed typo
Added note to CHANGES file