[TRANSLOG] Cut over to Path API

This commit also refactors `RAFReference` to work on top of a Channel instead of fetching the channel from the RandomAccessFile. The channel is created to truncate the file it opens too. This likely needs some documentation or we should allow the caller to pass the open options but I wanted to get this change out for review.
I think it would be better to pass a boolean in to this method, since it's ambiguous from the name of the method whether it sets a var (could be named `setDeleteOnClose()` if it were setting something) or actually does the deleting.