Puppet 4 disabled `source_permissions => use` for local sources on Windows

Puppet 4 disabled source_permissions => use for local sources on Windows. The rationale for remote sources is that POSIX permissions and ownership (which are inherently what the master will check) do not map well to Windows. That argument doesn't apply to local sources, however they were also disabled at the same time.

We should restore source_permissions => use as a valid use-case for local sources.