Update HistogramTypes in the Java API
Update HistogramTypes in the Java API

Summary:
This diff syncs the Histogram Types in the Java API with the ones in C++ API (`statistics.h`), and brings it up-to-date.

I also found that the enum ordering between Java and C++ has gotten out-of-sync, a few years back, with the addition of `SUBCOMPACTION_SETUP_TIME`. So updated the order as well.

`READ_NUM_MERGE_OPERANDS` added in #2373 is needed for Cassandra-on-RocksDB work.
Closes https://github.com/facebook/rocksdb/pull/2429

Differential Revision: D5215623

Pulled By: sagar0

fbshipit-source-id: bd136698c48197e53693275eb52acc9198ee5a4e

SunguckLee/RocksDB,bbiao/rocksdb,Andymic/rocksdb,SunguckLee/RocksDB,SunguckLee/RocksDB,bbiao/rocksdb,bbiao/rocksdb,Andymic/rocksdb,SunguckLee/RocksDB,bbiao/rocksdb,bbiao/rocksdb,Andymic/rocksdb,SunguckLee/RocksDB,SunguckLee/RocksDB,Andymic/rocksdb,bbiao/rocksdb,Andymic/rocksdb,SunguckLee/RocksDB,Andymic/rocksdb,SunguckLee/RocksDB,bbiao/rocksdb,bbiao/rocksdb,Andymic/rocksdb,Andymic/rocksdb