this is more consistent with other similar tools, and enables us to add something like a [copy:dev] section later, that will avoid copying dev files to production builds.
this is used by blogc-github-lambda and blogc-git-receiver.
even if we are translating some file names, for example to use a .xml file as directory index, we still need to upload the file to the real filename, to avoid automatically generated atom feeds produced by blogc-make pointing to wrong urls.