基于GO语言的PBFT共识算法

最近采用GO语言实现了一个PBFT共识算法的demo，主要用于展示算法的核心逻辑

github地址：https://github.com/w3liu/consensus/tree/master/pbft

1. 主节点定时出块（每1秒钟）

2. 共识流程：

    * propose - 主节点提议
    * vote - 从节点投票
    * preCommit - 所有节点预提交
    * commit - 提交，流程结束，进入下一个区块

3. 编译
```
make clean
make
```

4. 启动主节点
```
./pbft -c=./config/config.toml
```

5. 启动从节点
```
./pbft -c=./config/config1.toml
./pbft -c=./config/config2.toml
./pbft -c=./config/config3.toml
```
6. 输出
```
{"level":"info","ts":1600916693.3426318,"caller":"log/zap.go:20","msg":"block commit","height":1,"data":"This is a block data, height is 1."}
{"level":"info","ts":1600916703.341808,"caller":"log/zap.go:20","msg":"block commit","height":2,"data":"This is a block data, height is 2."}
{"level":"info","ts":1600916713.339083,"caller":"log/zap.go:20","msg":"block commit","height":3,"data":"This is a block data, height is 3."}
{"level":"info","ts":1600916723.3332858,"caller":"log/zap.go:20","msg":"block commit","height":4,"data":"This is a block data, height is 4."}
{"level":"info","ts":1600916733.341336,"caller":"log/zap.go:20","msg":"block commit","height":5,"data":"This is a block data, height is 5."}
...
```