Get transforms and spin off a task for each

This commit moves the tasks module to dispatch as it was clashing with
that tasks namespace.

We want to get all transforms that need running for this data set and
spin them out to a new task that will grab the data, run the transform
and write the new data.
Worker should get data set config once

We need to use the data set config in transforms and this will be the
same for the N sub tasks that are dispatched, so we should get it in the
entrypoint function.