Add More Benchmark Test

[qiuyuyin]

The performance of rosedb is not so clear. We don't know how it perform as a kv database, just add a benchmark like other kv db can help a lot to constract other kv database.

[roseduan]

There is a simple bench of rosedb: https://github.com/flower-corp/simple-bench

But as you said, it is not very clear, maybe we can add go-ycsb(https://github.com/pingcap/go-ycsb) test later.