Update README with development instructions

Signed-off-by: Matthew Peveler <[email protected]>

Author: MasterOdin

README.md

@@ -23,3 +23,28 @@ jobs:
     steps:
       - uses: submitty/action-pr-title@master
 ```
+
+## Development
+
+### Requirements:
+
+* NodeJS 12+
+
+### Setup
+
+```bash
+npm install
+```
+
+### Contributing
+
+For new code, you will need to:
+
+1. Write the code
+1. Lint the code (`npm run lint`) and test it (`npm run test`)
+
+After you're satisfied with the changes you've made, you will want to finally update the files under `dist/` with your change
+by running `npm run package`. Make sure to commit these changed files, as these are the files that are used when people utilize
+this action!
+
+With that done, create a PR!

package.json

@@ -1,13 +1,13 @@
 {
   "name": "action-pr-title",
   "version": "1.0.0",
-  "description": "",
+  "description": "GitHub action to validate PR titles meet our guidelines",
   "main": "lib/index.js",
   "scripts": {
     "build": "tsc",
     "lint": "eslint src test",
     "lint:fix": "prettier --write \"**/*.ts\"",
-    "package": "ncc build --source-map --license licenses.txt",
+    "package": "npm run build && ncc build --source-map --license licenses.txt",
     "test": "TS_NODE_PROJECT='./tsconfig.test.json' mocha --require ts-node/register --reporter spec --recursive './test/**/*.ts'",
     "prepare": "husky install"
   },