Created stats for users (number of users and list of newest users). Better separated the forums, who's online, and user stats. Use a Celery task to execute the new user stats processing. This addresses #194 and #238.

.poll-form {
    padding-bottom: 1em;
}
.poll-form ul {
    list-style: none;
    padding-bottom: 0.5em;
}
.poll-form li {
    padding: 0.5em 0 0.5em 0.5em;
}
dl.poll-result {
    width: 80%;
}