Another false start at JIST
 Removing the false start at JIST
Fleshing out functional package
Separating out the parallel aggregator complexity into its own file

- intend to create a less complicated single-thread version, too
Finish simple InThreadAggregatingIterator implementation
A new simpler implementation of parallel iteration based on a sometimes blocking queue
Reworking the API for parallelization

- Introduced Parallelizer object that can be shutdown
- Has same API as JavaReader, but produces parallelized type
collections.