Improve test for S3-Client
Make double encoding signing available

- some amazon services (like s3) apparently need to initialize the
  AWSV4Signer diffidently so and option was added to the props
  defaulting to the old behavior
Encode path when sending request with body
Fix encoding issues in responses

- returning the string here might cause problems for the marshallers
  when they want to handle the char encoding them self (like the xml
  decoders for example)
Support objects with odd names on S3
Merge pull request #9 from fidesmo/s3-improvments

Improve s3