18f538038a
Summary: Given that we have cut 5.15, we should bump the version number to the next version, i.e. 5.16. Also update HISTORY.md cc sagar0 Pull Request resolved: https://github.com/facebook/rocksdb/pull/4176 Differential Revision: D8977965 Pulled By: riversand963 fbshipit-source-id: 481d75d2f446946f0eb2afb7e94ef894c8c87e1e