Fix broken unit test around default pull queue for messages.
Add MessageProcessor and insert_messsage_processor to batcher

Add MessageProcessor Async object to the batcher module. This object will
insert a task to pull tasks off a pull queue. It will try to insert them
serially using a memcache marker based off a time frequency formula.

Add insert_messsage_processor function that wraps creating a MessageProcessor
and inserting it.
Removing helper function for batch processor.
Add bump_batch method for incremeting the batch count.

Increments memcahce buy a key.
Convert Context to take options kwargs.

To facilitate future extensions, switch from named insert_tasks
injection parameter to fetching it from options.  This will keep the API
cleaner as additional injection points are added.
Add `id` to Context.

`id` will be used to group asyncs withing the Context and also to
facilitate access to the Context's state once persistence is
implemented.