rsync flags
rsync flags

Fixes https://github.com/sbt/sbt/issues/5035

Currently `sbt` calls `rsync -a`, which expands to `-rlptgoD`, including `--group` and `--owner` flag that preserves the group and owner of the files. This drops the requirement since we just need to copy files around with the right timestamp.

sbt/sbt,sbt/sbt,xuwei-k/xsbt,xuwei-k/xsbt,sbt/sbt,xuwei-k/xsbt,sbt/sbt,sbt/sbt,sbt/sbt,mdedetrich/sbt,xuwei-k/xsbt,mdedetrich/sbt,sbt/sbt,mdedetrich/sbt,mdedetrich/sbt,mdedetrich/sbt,sbt/sbt-launcher-package,sbt/sbt-launcher-package,xuwei-k/xsbt,mdedetrich/sbt,mdedetrich/sbt