Fix utf-8 encoding issue for bucket lifecycle

- multi-byte prefixes need to be encoded in utf-8
  before they are sent to S3.
- Added XML declaration for the lifecycle.
- Added unit test to set and retrieve a bucket config which
  demonstrates the utf-8 issue.
- Note: AWS doesn't seem to work properly when retrieving
  the Japanese prefix. It comes back garbled. The request
  is however sending correctly encoded utf-8 according to
  a packet trace. I've left the final Assert commented out
  in the test case until AWS fixes the issue.