initial version of export-scripts

I have no tested it :)

scripts/export-scripts.js

+var fs = require('fs');
+
+if (!(
+  process.argv[2] === '--i-know-what-im-doing' &&
+  process.argv[3] === '--there-is-no-going-back'
+)) {
+  console.log(
+    'This command will copy all the scripts and configurations',
+    'from the create-react-app command to your directory.',
+    'You will be able to tweak and extend them but be aware that',
+    'this is a one way operation, there is no going back'
+  );
+  console.log(
+    'If you want to run this, please type the following command'
+  );
+  console.log(
+    '  npm run export-scripts --i-know-what-im-doing --there-is-no-going-back'
+  );
+  process.exit(1);
+}
+
+console.log('Extracting scripts...');
+
+var hostPath = __dirname;
+var selfPath = hostPath + '/node_modules/create-react-app-scripts';
+
+var files = [
+  'scripts',
+  '.webpack.config.dev.js',
+  '.webpack.config.prod.js',
+  '.babelrc',
+  '.eslintrc',
+];
+
+// Ensure that the host folder is clean and we won't override any files
+files.forEach(function(file) {
+  if (fs.existsSync(hostPath + '/' + file)) {
+    console.error(
+      '`' + file + '` already exists on your app folder, we cannot ' +
+      'continue as you would lose all the changes.',
+      'Please delete it (maybe make a copy for backup) and run this ' +
+      'command again.'
+    );
+    process.exit(1);
+  }
+});
+
+// Move the files over
+files.forEach(function(file) {
+  fs.renameSync(selfPath + '/' + file, hostPath + '/' + file);
+});
+
+var hostPackage = require(hostPath + '/package.json');
+var selfPackage = require(selfPath + '/package.json');
+
+// Copy over dependencies
+hostPackage.dependencies = hostPackage.dependencies || {};
+for (var key in selfPackage.dependencies) {
+  hostPackage.devDependencies[key] = selfPackage.dependencies[key];
+}
+
+delete hostPackage.dependencies['create-react-app-scripts'];
+
+// Update the script rules
+['start', 'build'].forEach(function(command) {
+  hostPackage.scripts[command] = 'node scripts/' + command + '.js local';
+});
+delete hostPackage['export-scripts'];
+
+fs.writeFileSync(hostPath + '/package.json', JSON.stringify(hostPackage, null, 2));
+
+// TODO: run npm install in hostPath
+
+// Move the src folder
+
+console.log('Done!');