beginning of p4

I will work on this more on the weekend, it’s not hard, but I need to
take some time to consider what I’m doing.
Revert "beginning of p4"

This reverts commit 0cc3a51e22b009b8b1d539087721e32a2fc3703b.
Not finished yet...

I’m still thinking about how to properly set up the conflicts tracker.

Done:
-initialize board & update conflicts
-print the board and the conflicts to the screen

Kind of done…:
-check whether a value causes conflicts if it is placed in a cell
-add a value to a cell, and update conflicts

Not done:
-clear a cell, and update conflicts
-check to see if the board has been solved (return true or false, and
print the result to the screen)