In project that have different source directories depending on the Scala version, it would be useful to have the header check run with `+`: `sbt +headerCheckAll`. Same goes for the `prePR` call to `headerCreateAll`.
In project that have different source directories depending on the Scala version, it would be useful to have the header check run with
+:sbt +headerCheckAll.Same goes for the
prePRcall toheaderCreateAll.