Hint system

[GoogleCodeExporter]

For those really difficult puzzles you've tried time & time again, it would 
be useful to implement a hint system.  I envision it as just turning the 
numbers red if you have a guess in the same row or column as that actual 
number, and turning just the actual number & and the same guess red.  At 
least then it wouldn't be just GIVING you the answer, you'd have to do work 
to even get to a point where this can be useful.  And I realize this allows 
you to fill every cell with every guess, and possibly hint your way to a 
solution-- but if you want to skip the challenge, why are you playing?  And 
the Hint button would only show you the NEXT hint, not all of them.  Just a 
thought to help me get over the hurdle on some doozies...

Original issue reported on code.google.com by [email protected] on 7 Mar 2010 at 5:09