docs: update README installation instructions and badges

- Remove badges and update installation instructions in README.md

Signed-off-by: Bo-Yi Wu <appleboy.tw@gmail.com>

README.md

@@ -1,13 +1,9 @@
 # drone-lambda
 
 [![GoDoc](https://godoc.org/github.com/appleboy/drone-lambda?status.svg)](https://godoc.org/github.com/appleboy/drone-lambda)
-[![Build Status](https://cloud.drone.io/api/badges/appleboy/drone-lambda/status.svg)](https://cloud.drone.io/appleboy/drone-lambda)
 [![codecov](https://codecov.io/gh/appleboy/drone-lambda/branch/master/graph/badge.svg)](https://codecov.io/gh/appleboy/drone-lambda)
 [![Go Report Card](https://goreportcard.com/badge/github.com/appleboy/drone-lambda)](https://goreportcard.com/report/github.com/appleboy/drone-lambda)
 [![Docker Pulls](https://img.shields.io/docker/pulls/appleboy/drone-lambda.svg)](https://hub.docker.com/r/appleboy/drone-lambda/)
-[![microbadger](https://images.microbadger.com/badges/image/appleboy/drone-lambda.svg)](https://microbadger.com/images/appleboy/drone-lambda "Get your own image badge on microbadger.com")
-[![Release](https://github-release-version.herokuapp.com/github/appleboy/drone-lambda/release.svg?style=flat)](https://github.com/appleboy/drone-lambda/releases/latest)
-[![Build status](https://ci.appveyor.com/api/projects/status/cuioqombam9yufdy?svg=true)](https://ci.appveyor.com/project/appleboy/drone-lambda)
 
 Deploying Lambda code with drone CI to an existing function. The plugin automatically deployes a serverless function to AWS Lambda from a zip file located in an S3 bucket. This plugin does not handle creating or uploading the zip file.
 
@@ -22,7 +18,7 @@ The pre-compiled binaries can be downloaded from [release page](https://github.c
 With `Go` installed
 
 ```bash
-go get -u -v github.com/appleboy/drone-lambda
+go install github.com/appleboy/drone-lambda@latest
 ```
 
 or build the binary with the following command: