Get everything using celery

[eristoddle]

Queues and Threads and Pypubsub are being used in the ticker, market_watcher, and PortfolioBase strategy like the original Titan algorithms. These can be replaced with celery, celerybeat and Redbeat or something similar to Redbeat. See how the harvesters run.

This issue's priority is only as high as the current method's resource usage which I have yet to investigate.