use \hiderowcolors to address possible colortbl bug

[Alex-Jordan]

If you have nested niceTables (say a DataTable within a LayoutTable) there seems to be a bug with the colortbl package's \rowcolor command, and if you use it in the inner table, you end up coloring more than just the one row. You can see this with:

DOCUMENT();
loadMacros(qw(PGstandard.pl PGML.pl niceTables.pl));
BEGIN_PGML
[@LayoutTable([[
    DataTable([
        [['', rowcolor => 'lightgray'], 'A', 'B'],
        [1, 2, 3],
    ])
]])@]*
END_PGML
ENDDOCUMENT();

which should only make the first row gray, but what I think is a bug is making both rows gray.

This commit addresses that by applying \hiderowcolors at the end of any row that set a row color. Note that you can give the second row a color, and that still works; this is not permanently taking away row colors.

[pstaabp]

Saw the bug and this fixes it.

[drgrice1]

Looks good. This fixes the problem which can be seen with the MWE on the develop branch.

[drgrice1]

I will merge this since the hotfix of this was merged. This is the last one that was supposed to be merged.