Add badges and Development section to README

Author: lambdalisue

README.md

@@ -1,8 +1,10 @@
 # unknownutil
 
+[![npm](http://img.shields.io/badge/available%20on-npm-lightgrey.svg?logo=npm&logoColor=white)](https://www.npmjs.com/package/unknownutil)
 [![deno land](http://img.shields.io/badge/available%20on-deno.land/x-lightgrey.svg?logo=deno)](https://deno.land/x/unknownutil)
 [![deno doc](https://doc.deno.land/badge.svg)](https://doc.deno.land/https/deno.land/x/unknownutil/mod.ts)
 [![Test](https://github.com/lambdalisue/deno-unknownutil/workflows/Test/badge.svg)](https://github.com/lambdalisue/deno-unknownutil/actions?query=workflow%3ATest)
+[![npm version](https://badge.fury.io/js/unknownutil.svg)](https://badge.fury.io/js/unknownutil)
 
 A utility pack for handling `unknown` type.
 
@@ -141,6 +143,40 @@ ensureLike({}, b); // Now 'b' is 'Record<string, unknown>'
 ensureLike({ foo: "", bar: 0 }, b); // Now 'b' is '{foo: string, bar: number}'
 ```
 
+## Development
+
+Lint code like:
+
+```text
+make lint
+```
+
+Format code like
+
+```text
+make fmt
+```
+
+Check types like
+
+```text
+make type-check
+```
+
+Run tests like:
+
+```text
+make test
+```
+
+Publish new version with:
+
+```
+npm version {major/minor/patch}
+npm publish
+git push --tags
+```
+
 ## License
 
 The code follows MIT license written in [LICENSE](./LICENSE). Contributors need