Compute the metrics for the project activity section of the enriched
    github issues index.

    Returns a dictionary containing a "metric" key. This key contains the
    metrics for this section.

    :param index: index object
    :param start: start date to get the data from
    :param end: end date to get the data upto
    :return: dictionary with the value of the metrics

def project_activity(index, start, end):
    """Compute the metrics for the project activity section of the enriched
    github issues index.

    Returns a dictionary containing a "metric" key. This key contains the
    metrics for this section.

    :param index: index object
    :param start: start date to get the data from
    :param end: end date to get the data upto
    :return: dictionary with the value of the metrics
    """

    results = {
        "metrics": [OpenedIssues(index, start, end),
                    ClosedIssues(index, start, end)]
    }

    return results