code: public Pairtree getPrefixedPairtree(final String aPrefix, final String aBucket, final String aBucketPath,
              final String aAccessKey, final String aSecretKey) {
          return new S3Pairtree(aPrefix, myVertx, aBucket, aBucketPath, aAccessKey, aSecretKey);
      }
docs: Creates a Pairtree, with the supplied prefix, using the supplied S3 bucket and internal bucket path.
  
  @param aPrefix A Pairtree prefix
  @param aBucket An S3 bucket
  @param aBucketPath A path in the S3 bucket to the Pairtree root
  @param aAccessKey An AWS access key
  @param aSecretKey An AWS secret key
  @return A Pairtree