Initial commit
Basic grid manipulation
More grid handling
Working mark function
Works. Slow as hell, but anyway.
Untabify!
Row-unique heuristic
Column-unique heuristic
Square unique heuristic.

Also, harder example because this one is pretty good.
Prints backtrace!
7-star problem from TEK-lehti.

Seems to require one lucky guess to solve.
5-star problem from HS.

This is harder than the 7-star one.
Joined search path pruning w/ hash set of states
Closer to standard interface
More samples
Refactoring for move to codekata repository
Merges sudoku to this public showoff