remove filtering of directory markers in s3a RenameOperation

S3A RenameOperation tries to filter out renaming intermediate directory markers so as to avoid retaining them when copying from an authoritiative dir to a non-auth one. we did this to support installations where dir marker retention was only enabled for auth dirs

• nobody, AFAIK, does this..it is all or nothing
• all recent hadoop releases, including earlier branches, is now marker aware
• the extras complexity makes debugging rename problems harder.

let's just cut it out.