* replace media workers with just runners.WorkerPool, move to state structure, use go-sched for global task scheduling
* improved code comment
* fix worker tryUntil function, update go-runners/go-sched
* make preprocess functions package public, use these where possible to stop doubled up processing
* remove separate emoji worker pool
* limit calls to time.Now() during media preprocessing
* use Processor{} to manage singular runtime of processing media
* ensure workers get started when media manager is used
* improved error setting in processing media, fix media test
* port changes from processingmedia to processing emoji
* finish code commenting
* finish code commenting and comment-out client API + federator worker pools until concurrency worker pools replaced
* linterrrrrrrrrrrrrrrr
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Signed-off-by: kim <grufwub@gmail.com>
