Add a way to skip determinePartitions for IndexTask by manually
specifying numShards.

switch back to noop task, its confusing to have a reinvest task that
does nothing.
fix compilation

committed it by mistake.

can be used to ingest data from multiple sources.

Optimize choosing shardSpec for Hash Partitions

add an optional delay for how long it takes to drop a segment, fixes all manners of inconsistent issues