Simplify new version release steps (#61)

* Simplify new version release steps

Suggest use of npm version command to bump version and create new
new git tag and commit.

Use version script to update CDN url referenced in README.md file.

Add more pre-step scripts for basic workflows.

* Add clean script and use before publication

Also limit packaged files to the common ones and newly generated
files under dist/ folder.

Author: bz2

CONTRIBUTING.md

@@ -48,12 +48,12 @@ the one above, the [Software Grant and Corporate Contributor License Agreement].
 
 ## Creating a new release
 
-* find and replace the version number package.json and commit
-* create a new git tag: `git tag v0.0.x`
-* push tag `git push --tags`
-* Create a [GitHub Release]
-* update on npm: `npm publish`
-* update the README to use this new published version in setup instructions and commit
+From master branch with all required changes landed and pulled:
+
+* Run `npm version minor -m 'Release %s'` with semver component as needed.
+* Push commit and new tag with `git push --tags`.
+* Create a [GitHub Release].
+* Publish new package to npm registry with `npm publish`.
 
 
 [npm]: https://www.npmjs.com/

package.json

@@ -4,16 +4,24 @@
   "description": "Experimental client-side JavaScript library to report errors to Stackdriver Error Reporting",
   "main": "stackdriver-errors.js",
   "scripts": {
+    "clean": "rimraf dist/",
     "dist": "gulp dist",
     "lint": "eslint --ignore-path .gitignore .",
+    "prebuild": "npm run test",
     "prepare": "npm run dist",
+    "prepublish": "npm run clean",
+    "pretest": "npm run lint",
     "start": "gulp demo && http-server ./dist -o",
-    "test": "npm run lint && mocha -r test/setup.js test/test.js"
+    "test": "mocha -r test/setup.js test/test.js",
+    "version": "sed -i s/@[0-9.]\\\\{5,\\\\}/@${npm_package_version}/g README.md && git add README.md"
   },
   "repository": {
     "type": "git",
     "url": "https://github.com/GoogleCloudPlatform/stackdriver-errors-js"
   },
+  "files": [
+    "dist/"
+  ],
   "keywords": [
     "stackdriver",
     "error",
@@ -37,6 +45,7 @@
     "gulp-uglify": "^3.0.1",
     "http-server": "^0.11.1",
     "mocha": "^5.2.0",
+    "rimraf": "^2.6.2",
     "sinon": "^7.1.1"
   },
   "dependencies": {