add check-coc and add devDependency @cocreate/cli

Author: frankpagan

package.json

@@ -28,6 +28,7 @@
     "build": "NODE_ENV=production npx webpack --config webpack.config.js",
     "dev": "npx webpack --config webpack.config.js --watch",
     "docs": "node ./node_modules/@cocreate/docs/src/index.js",
+    "postinstall": "node ./node_modules/@cocreate/cli/check-coc.js",
     "dist": "node --version"
   },
   "repository": {