docs(readme): update readme with nightly build instructions (#1510)

Author: liamdebeasi

Diff for: README.md

@@ -1,5 +1,6 @@
 [![npm version](https://img.shields.io/npm/v/@ionic/app-scripts.svg)](https://www.npmjs.com/package/@ionic/app-scripts)
 [![Circle CI](https://circleci.com/gh/ionic-team/ionic-app-scripts.svg?style=shield&circle-token=:circle-token)](https://circleci.com/gh/ionic-team/ionic-app-scripts)
+
 # Ionic App Scripts
 
 Helper scripts to get [Ionic apps](https://ionicframework.com/) up and running quickly (minus the config overload).
@@ -251,17 +252,27 @@ We welcome any PRs, issues, and feedback! Please be respectful and follow the [C
 
 We use Node 6, and NPM 5 for contributing.
 
+### Publish a Nightly Build
+
+1. Run `npm run build` to generate the `dist` directory
+2. Run `npm run test` to validate the `dist` works
+3. Tick the `package.json` version
+4. Run `npm run nightly` to generate a nightly build on npm
+
+
+
 ### Publish a release
 
 Execute the following steps to publish a release:
 
-1. Run `npm run build` to generate the `dist` directory
-2. Run `npm run test` to validate the `dist` works
-3. Temporarily tick the `package.json` version
-4. Run `npm run changelog` to append the latest additions to the changelog
-5. Manually verify and commit the changelog changes. Often times you'll want to manually add content/instructions
-6. Revert the `package.json` version to the original version
-7. Run `npm version patch` to tick the version and generate a git tag
-8. Run `npm run github-release` to create the github release entry
-9. Run `npm publish` to publish the package to npm
-10. `git push origin master` - push changes to master
+1. Ensure your branch has been merged into `master`
+2. Run `npm run build` to generate the `dist` directory
+3. Run `npm run test` to validate the `dist` works
+4. Temporarily tick the `package.json` version
+5. Run `npm run changelog` to append the latest additions to the changelog
+6. Manually verify and commit the changelog changes. Often times you'll want to manually add content/instructions
+7. Revert the `package.json` version to the original version
+8. Run `npm version patch` to tick the version and generate a git tag
+9. Run `npm run github-release` to create the github release entry
+10. Run `npm publish` to publish the package to npm
+11. `git push origin master` - push changes to master