Enhance PHP Gandi API example

As title, it seems that the PHP Gandi API has been inactive for the while.

I think it's time to update/enhance them and my thoughts are as follows:

• Consider splitting api-examples to every api-example with different programming language. I think this can be independent and easy to maintain.
• It can split these api-examples to python-api-example, php-api-example and so on.

Once this issue is accepted, I think I can help the php-api-examples.