function getUniqueId(wizard)
{
    var uniqueId = wizard.data("uid");

    if (uniqueId == null)
    {
        uniqueId = wizard._id();
        if (uniqueId == null)
        {
            uniqueId = "steps-uid-".concat(_uniqueId);
            wizard._id(uniqueId);
        }

        _uniqueId++;
        wizard.data("uid", uniqueId);
    }

    return uniqueId;
}
Gets or creates if not exist an unique id from the given wizard instance.

@static
@private
@method getUniqueId
@param wizard {Object} A jQuery wizard object
@return {String} Returns the unique id for the given wizard