cssColorClasses should be configurable

[hexmode]

Right now this is hard-coded into the class:

    public function __construct ( Title $title ) {

        $this->mTitle = $title;
        $this->cssColorClasses = array(
            'excellent',
            // 'good',
            'okay',
            // 'warning',
            'danger',
        );
    }

Instead the config object should be read. Defaults should be kept in extension.json.

[hexmode]

Documentation should also be improved.

Right now, from looking at the code, it looks like you have two different arrays that determine which color class to use:

$GLOBALS['egWatchAnalyticsWatchQualityColors'] = array(
    // 6,   // score over 6   = excellent
    // 4,   // score over 4   = good
    // 1.5, // score over 1.5 = okay
    // 0.5, // score over 0.5 = not so good
         // score < 0.5    = bad

    5,   // score over 5   = excellent
    1.5, // score over 1.5 = okay
    // score < 1.5
);
$GLOBALS['egWatchAnalyticsReviewStatusColors'] = array(
    // 4, // 5+ reviews = excellent
    // 3, // 4 reviews  = good
    // 2, // 3 reviews  = okay
    // 1, // 2 reviews  = not so good
    //    // 0 or 1     = BAD

    4, // score over 4 = good
    2, // score over 2 = okay
    // 0 or 1 = BAD
);

This could be changed to something like:

$egWatchAnalyticsWatchQualityColors = [
    5     => 'excellent',
    1.5  => 'okay',
        null    => 'danger',
];
$egWatchAnalyticsReviewStatusColors' = [
    4  => 'excellent',
    2  => 'okay',
    null => 'danger'
];

I use null instead of 0 to allow for the possibility of negative scores.

Besides avoiding the hard-coding, it avoids problem where the number of cssColors wouldn't match the number of levels available -- a potentially subtle way to introduce problems.