- Update rocksdb submodule to revision
  d616ebea23fa88cb9c2c8588533526a566d9cfab
- Normally this should be done by doing a merge from upstream
  MyRocks, but now we are just updating rocksdb, MyRocks merge will
  follow later.
- Apply a part of 4f6f072f6c74513087004755508eb6d6c432c5c1
  use_direct_writes was renamed to use_direct_io_for_flush_and_compaction
- Update build_rocksdb.cmake - RocksDB have moved files around