Refactor RateLimiter so that if Redis is not running, everything still runs normally (minus the rate limiting protection). My assumption that creating a Redis connection would throw an exception if Redis wasn't running was wrong. The exceptions actually occur when you issue a command. This is for #224.

div.potd-details {
    text-align: center;
}
div.potd-details p.caption {
    font-weight: bold;
}
div.potd-details p.details {
    font-style: italic;
    font-size: smaller;
}