Also alter CrawledDocument to not require String parsing of the underlying byte[] data. This should reduce the number of large memory allocations quite significantly, hopefully reducing the GC churn a bit.
Replaces Parquet output and processing with the new Slop-based format. Includes data migration functionality, updates to handling and writing of crawl data, and introduces support for SLOP in domain readers and converters.
Refactoring keyword extraction to extract spans information.
Modifying the intermediate storage of converted data to use the new slop library, which is allows for easier storage of ad-hoc binary data like spans and positions.
This is a bit of a katamari damacy commit that ended up dragging along a bunch of other fairly tangentially related changes that are hard to break out into separate commits after the fact. Will push as-is to get back to being able to do more isolated work.
