Add per-queue admin settings for queues in the queue group

The admin settings currently assume that all queues in the queue group use the same queue configuration. However, each queue should be able to configure its own specific settings. For example, most of the queues in the queue group can use the default queue group number of workers, but each queue should be able to increase/decrease that amount as necessary to fulfill its workload. There can be an arbitrary number of queues, so it has to take into account the ability to send an arbitrary number of queue-specific configurations rather than assume that there's one remote queue config and one remote queue group config.

As part of this, the admin UI's Amboy section should be reorganized and tidied up since the options global remote queue and queue group options are mixed together confusingly. At the very least, they should be organized into sub-headings with in the Amboy section for human readability.