Patch for input colors (correct/incorrect)

This rewrites the color.js file that adds colors to the input fields for correct/incorrect colors.  It requires the [corresponding pull](https://github.com/openwebwork/pg/pull/146) request from pg in order to work.

Prior to this patch, the colors for MathObject `ans_array` calls (for Matrix, Vector, Point) only colored the first entry.  This should resolve that.

Also, MultiAnswer objects with `singleResults=>1` only colored the first blank.  This should resolve that as well.  Mixing MultiAnswer with Matrix Arrays should color properly as well.

Test cases are of the form:

```
loadMacros("parserMultiAnswer.pl");

Context("Matrix");
$M = Matrix([1,2],[3,4]);
$V = Vector(1,2,3);

$ma = MultiAnswer($M,$V)->with(
  singleResult => 1,
  checker => sub {
    my ($correct,$student) = @_;
    my ($c1,$c2) = @$correct;
    my ($s1,$s2) = @$student;
    return (1,1) if $c1 == $s1 && $c2 == $s2;
    return (1,0) if $c1 == $s1;
    return (0,1) if $c2 == $s2;
    return (0,0);
  }
);

BEGIN_TEXT
\{$ma->ans_array\} and \{$ma->ans_array\}
END_TEXT

ANS($ma->cmp);
```

One should also use `singleResult=>0`, and try with PopUp and RadioButton objects as well.