Merge pull request #150 from gplanchat/patch-1

Fixed version constraints of Guzzle6 client

Author: ahocquard

README.md

@@ -33,7 +33,7 @@ $ curl -s http://getcomposer.org/installer | php
 
 Then, run the following command to require the library:
 ```bash
-$ php composer.phar require akeneo/api-php-client php-http/guzzle6-adapter
+$ php composer.phar require akeneo/api-php-client php-http/guzzle6-adapter:^1.1
 ```
 
 If you want to use another HTTP client implementation, you can check [here](https://packagist.org/providers/php-http/client-implementation) the full list of HTTP client implementations.