Allow Highlighting of Numbers/Squares

[GoogleCodeExporter]

Especially for harder puzzles, it is useful to be able to highlight
numbers/squares. There are 2 requests here:

1. Allow the user to highlight everywhere a number is used (whether in
notes or solved for square).

2. Let the user highlight squares they wish to (preferably with different
colors), so that they can use simple coloring techniques to eliminate
possibilities.

Original issue reported on code.google.com by LutzR...@gmail.com on 2 Sep 2009 at 8:16

[GoogleCodeExporter]

I've separated point 2 into the issue #40

Original comment by romario...@gmail.com on 2 Oct 2009 at 7:22

[GoogleCodeExporter]

Hi, becouse of the lack of highlighting of numbers i stopped using opensudoku. 
For harder puzzles it's very important feature.

Original comment by racoon.k...@gmail.com on 11 Oct 2010 at 11:13

[GoogleCodeExporter]

I would just like to add my support for this issue/enhancement. I, 
particularly, would love highlighting of all the cells that contain any version 
of the selected number in "single number" input method. I have a hard time 
keeping track of numbers otherwise...

Original comment by Cavall...@gmail.com on 15 Dec 2010 at 10:11

[GoogleCodeExporter]

I was just about to add this feature request myself. So I give this suggestion 
my vote.

Original comment by fetm...@gmail.com on 6 Sep 2011 at 6:49