[Finder] Add info about possibilities offered by SplFileInfo

src/Symfony/Component/Finder/README.md

@@ -18,6 +18,10 @@ Finder finds files and directories via an intuitive fluent interface.
         print $file->getRealpath()."\n";
     }
 
+The resulting contents of the iterator are instances of [SplFileInfo][1]. You can 
+thus use all of SplFileInfo's methods (getPerms(), getSize(), etc) on them. See
+[the API documentation][2] or the [web tutorial][3] for more.
+
 But you can also use it to find files stored remotely like in this example where
 we are looking for files on Amazon S3:
 
@@ -39,3 +43,6 @@ You can run the unit tests with the following command:
     $ composer.phar install
     $ phpunit
 
+[1]: http://php.net/splfileinfo
+[2]: http://api.symfony.com/2.5/Symfony/Component/Finder/SplFileInfo.html
+[3]: http://symfony.com/doc/current/components/finder.html#usage