v0.9.2

Main feature and update

1. [network] Optimizing network messages and network services. (#1804)
2. [jsonrpc] JSON rpc support rate limit (#1824)
3. [network] p2p rpc support rate limit (#1833)
4. [sync & security] Report peer's reputation based on verify result when syncing, disconnect malicious nodes (#1837)
5. [jsonrpc] Add account.sign_txn_request api (#1839)
6. [chain] Refactor block verify logic (#1840)
7. [stdlib] Add peer_to_peer_batch script for bulk transfers and account creation (#1847)
8. [jsonrpc] Refactor and optimize pubsub (#1856)
9. [storage config] Support setting maximum number of open files (#1855)
10. [network config] Support for mdns config for node discovery on LAN (#1845)
11. [sync] Refactor and optimize network synchronization, improve synchronization speed and enhance synchronization fault tolerance mechanism. Support skipping PoW difficulty verify when sync from trust peers. (#1824) ([#1826](https://github.com/starcoinorg/starcoin/ pull/1846)) (#1857) ([#1848](https://github.com/starcoinorg/starcoin/pull/ 1848))

中文说明

1. [network] 优化网络消息以及网络服务. (#1804)
2. [jsonrpc] JSON rpc 接口增加 rate limit 设置(#1824)
3. [network] p2p rpc 接口增加 rate limit 设置(#1833)
4. [sync & security] 同步时根据校验结果汇报 peer 的 reputation, 断开恶意节点(#1837)
5. [jsonrpc] 新增 account.sign_txn_request 接口，方便无 sdk 的编程语言组装以及签名交易(#1839)
6. [chain] 重构 chain 模块中的区块校验逻辑 (#1840)
7. [stdlib] Add peer_to_peer_batch 脚本方便批量转账以及创建账号 (#1847)
8. [jsonrpc] 重构以及优化 pubsub (#1856)
9. [storage config] 限制以及支持设置最大打开文件数 (#1855)
10. [network config] 支持 mdns 开关方便局域网内的节点发现 (#1845)
11. [sync] 重构以及优化网络同步,提高同步速度，增强同步容错机制。支持从信任节点同步时跳过 PoW 难度校验 (#1824) (#1826) (#1857) (#1848)