// 0: local-node
	// 1: master-worker
	RunMode RunMode `toml:"run_mode"`
	// serve http port
	HttpPort string `toml:"http_port"`
	// serve websocket port
	WsPort string `toml:"ws_port"`
    // log out level:
    // panic, fatal, error, warn, info, debug, trace
    LogLevel string `toml:"log_level"`
    
    LeiLimit uint64 `toml:"lei_limit"`
- Runmode: 为节点运行方式, 0为单节点形式运行,1为master-worker形式运行(master-worker形式暂不支持)
- HttpPort: http监听地址,服务于外部调用的端口配置。
- WsPort: websocket监听地址,服务于外部调用的端口配置。 
- LogLevel: 打印Log的等级,从上到下依次有 panic,fatal,error,warn,info,debug,trace
- LeiLimit: 每个区块里可以被消耗的 lei的上限
run_mode = 0
http_port = "7998"
ws_port = "8998"
log_level = "info"
lei_limit = 50000