Updated Services classes to use the new AWS SDK for PHP

**IMPORTANT:** I did not even run this code, so I cannot guarantee it's full correctness. However, it should be a good example for you. Unfortunately, we don't have SNS support in SDK2, so I left that one as is. SDK1 and SDK2 can co-exist though, so there shouldn't be a problem with that. Let me know if you have any other questions.