Modified entrypoint to step and render at the same time
Squashed commit of the following:

    Moved code to adjust point to display point to its own namespace
    Threaded total-rows through draw functions so it can be used to draw the board relative to last row
Added repl history
Added youtube video
Refactored code to remove warnings
Simplified `occupied-at?`
Trying to add falling blocks to occupied points
Fixed problem with all-occupied-pts
Added a test to confirm behavior of swapping
Changed order of falling block creation/resolution to give player opportunity to swap them