memo: Add doc of batch tx. [skip ci]
- [Log Management](system_management/log.md)
- [System Management](system_management/sys.md)
- [Snapshot](system_management/snapshot.md)
+ - [Batch Tx](system_management/batch_tx.md)
- Json-RPC Guide
- [Json-RPC List](rpc_guide/rpc.md)
- [Json-RPC Parameters and Returns](rpc_guide/rpc.md)
