Update file structure in README (facebook#664)

Author: sstruct

README.md

@@ -51,14 +51,14 @@ Inside that directory, it will generate the initial project structure and instal
 my-app/
   README.md
   index.html
-  favicon.ico
   node_modules/
   package.json
   .gitignore
   src/
     App.css
     App.js
     App.test.js
+    favicon.ico
     index.css
     index.js
     logo.svg

template/README.md

@@ -80,13 +80,13 @@ After creation, your project should look like this:
 my-app/
   README.md
   index.html
-  favicon.ico
   node_modules/
   package.json
   src/
     App.css
     App.js
     App.test.js
+    favicon.ico
     index.css
     index.js
     logo.svg
@@ -95,7 +95,7 @@ my-app/
 For the project to build, **these files must exist with exact filenames**:
 
 * `index.html` is the page template;
-* `favicon.ico` is the icon you see in the browser tab;
+* `src/favicon.ico` is the icon you see in the browser tab;
 * `src/index.js` is the JavaScript entry point.
 
 You can delete or rename the other files.