wip on new name indexing strategy
add progress bars to prototype log-based name indexing
make only one log file for every 1024 buckets
make the new generate-names algorithm the only one
throw out HashStore stream_set and related code
make the max open filehandles settable in HashStore constructor
update release notes
choose the number of sort logs intelligently based on how much bucket
cache we can use, compress sort logs if --compress option is passed
bugfix to name indexing
tweak gzipped file size estimation
be a bit less conservative on memory usage
expand on release notes, move from minor to major
Merge branch 'generate-names-perf'