Change README for bc package

README.md

@@ -9,3 +9,26 @@ A blockchain implementation in Go, as described in these articles:
 5. [Addresses](https://jeiwan.cc/posts/building-blockchain-in-go-part-5/)
 6. [Transactions 2](https://jeiwan.cc/posts/building-blockchain-in-go-part-6/)
 7. [Network](https://jeiwan.cc/posts/building-blockchain-in-go-part-7/)
+
+# Quick Start
+
+## Download and install
+
+    go get github.com/richardweiyang/blockchain_go
+
+## Create file `main.go`
+```go
+package main
+
+import "github.com/richardweiyang/blockchain_go"
+
+func main() {
+	cli := bc.CLI{}
+	cli.Run()
+}
+```
+#### Build and run
+
+    go build main.go
+    ./main
+