- Get the suite to work with dynamically-linked plugin (ha_rocksdb.so)
- Due to the push to keep everything MyRocks-related in storage/rocksdb,
  there is no mysql-test/include/have_rocksdb.* anymore.
  Make a copy of storage/rocksdb/mysql-test/rocksdb/include/have_rocksdb*,
  hopefully these files wont be changed [often].
- Maria-fication of rocksdb_persistent_cache_path test.