Fix typo introduced in 4c38808d92b95.

The variable name is '$^O' not '-$^O'.  This meant File::Copy::move
didn't put the file in the current working directory when the to
argument had no path component.
Revert "Unix compatibility mode" in File::Copy on VMS.

This backs out the changes introduced in fc06fdeb76c89.  On
reflection, it doesn't make any sense to support what is actually
a Unix *report* mode in an API that does not report filenames.

File::Copy just needs to supply names to the underlying copy
functions that they can operate on.  How those names are presented
is of no concern here as we don't present them to the caller.
Simplify and clarify VMS specifics in File::Copy.

4c38808d92b95 added some logic to make a "to" path with no
directory component inherit from the current working directory
rather than the directory portion of the "from" path.  It also
added a trailing dot to make null file types unambiguous.  But
the comments emphasized the latter and made no mentin of the
former, and the implementation was unnecessarily complex.
Bump File::Copy to version 2.29.