code: function resolveBase(app) {
      const paths = [
        { name: 'base', path: path.resolve(cwd, 'node_modules/base') },
        { name: 'base-app', path: path.resolve(cwd, 'node_modules/base-app') },
        { name: 'assemble-core', path: path.resolve(cwd, 'node_modules/assemble-core') },
        { name: 'assemble', path: path.resolve(cwd, 'node_modules/assemble') },
        { name: 'generate', path: path.resolve(cwd, 'node_modules/generate') },
        { name: 'update', path: path.resolve(cwd, 'node_modules/update') },
        { name: 'verb', path: path.resolve(cwd, 'node_modules/verb') },
        { name: 'core', path: path.resolve(__dirname, '..') }
      ];
  
      for (const file of paths) {
        if (opts.app && file.name === opts.app && (app = resolveApp(file))) {
          return app;
        }
      }
  
      if (opts.app) {
        app = resolveApp({
          name: opts.app,
          path: path.resolve(cwd, 'node_modules', opts.app)
        });
      }
      return app;
    }
docs: Resolve the "app" to use