[cr] add contributing guide and publish scripts

Author: jewbetcha

CONTRIBUTING.md

@@ -0,0 +1,15 @@
+# Contributing guide
+
+1. Install dependencies
+
+```
+npm i
+```
+
+2. Run tests in watch mode
+
+```
+npm run test:watch
+```
+
+3. For any new features, add new tests

package.json

@@ -27,6 +27,7 @@
   "scripts": {
     "test": "jest",
     "test:watch": "jest --watch",
-    "build": "esbuild src/index.js --bundle --platform=node --outfile=dist/index.js "
+    "build": "esbuild src/index.js --bundle --platform=node --outfile=dist/index.js",
+    "publish": "npm build && npm publish"
   }
 }