Hint the default index.js path (#81)

* Hint the default index.js path

* Update ReactNativeGenerator.js

Author: dunglas

src/generators/ReactGenerator.js

@@ -50,7 +50,7 @@ export default class extends BaseGenerator {
       resource.title
     );
     console.log(
-      "Paste the following definitions in your application configuration:"
+      "Paste the following definitions in your application configuration (`client/src/index.js` by default):"
     );
     console.log(
       chalk.green(`

src/generators/ReactNativeGenerator.js

@@ -44,7 +44,7 @@ export default class extends BaseGenerator {
       resource.title
     );
     console.log(
-      "Paste the following definitions in your application configuration:"
+      "Paste the following definitions in your application configuration (`client/src/index.js` by default):"
     );
     console.log(
       chalk.green(`