Use "npm-run-all" to run scripts

[npm-run-all](https://github.com/mysticatea/npm-run-all) is a cross-browser approach to running npm tasks in series (`-s`) or parallel (`-p`). Rather than using a platform specific method to run scripts (e.g. `&&`), npm-run-all will work on all platforms and supports using Yarn if running with Yarn. I made a guess as to whether certain scripts should be run in series or parallel but feel free to change if my choices aren't optimal.

package.json

@@ -30,6 +30,7 @@
     "jest": "^20.0.4",
     "jest-cli": "^20.0.4",
     "lerna": "^2.1.1",
+    "npm-run-all": "^4.1.2",
     "plop": "^1.8.1",
     "prettier": "^1.9.2",
     "prettier-eslint-cli": "4.2.x",
@@ -41,15 +42,16 @@
   },
   "private": true,
   "scripts": {
-    "bootstrap": "yarn && npm run check-versions && lerna run prepublish",
+    "bootstrap": "npm-run-all -s install check-versions prepublish",
     "check-versions": "babel-node scripts/check-versions.js",
-    "format": "npm run format-packages && npm run format-cache-dir && npm run format-www && npm run format-examples && npm run format-scripts && npm run format-markdown",
+    "format": "npm-run-all -p format-packages format-cache-dir format-www format-examples format-scripts format-markdown",
     "format-cache-dir": "prettier-eslint --write \"packages/gatsby/cache-dir/*.js\"",
     "format-examples": "prettier-eslint --write \"examples/**/gatsby-node.js\" \"examples/**/gatsby-config.js\" \"examples/**/src/**/*.js\"",
     "format-packages": "prettier-eslint --write \"packages/*/src/**/*.js\"",
     "format-scripts": "prettier-eslint --write \"scripts/**/*.js\"",
     "format-markdown": "prettier --write \"**/*.md\" --semi",
     "format-www": "prettier-eslint --write \"www/*.js\" \"www/src/**/*.js\"",
+    "install": "yarn",
     "jest": "jest",
     "lerna": "lerna",
     "lint": "eslint --ext .js,.jsx packages/**/src",
@@ -59,10 +61,10 @@
     "publish-canary": "lerna publish --canary --yes",
     "publish-next": "lerna publish --npm-tag=next",
     "remotedev": "remotedev --hostname=localhost --port=19999",
-    "test": "yarn lint && yarn jest",
+    "test": "npm-run-all -s lint jest",
     "test:update": "jest --updateSnapshot",
     "test:watch": "jest --watch",
-    "test_bkup": "npm run lint && npm run test-node && npm run test-integration",
+    "test_bkup": "npm-run-all -s lint test-node test-integration",
     "watch": "lerna run watch --no-sort --stream --concurrency 999"
   },
   "workspaces": [