For #242, move the updating of the POTD sequence into a new signals module. When photos are deleted from the admin changelist in bulk, the individual delete() functions on the photo objects is not called. However, the post_delete signal is called for each object.

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;
}