fix the top-level directory path of imported CVS modules

CVS modules were imported with the a top-level directory which
matched the module name. For a CVS origin such as
rsync://cvs.savannah.gnu.org/sources/dino/dino
the top-level directory contained a single directory called "dino"
with all expected files and directories residing inside this directory.
E.g. the dino project's top-level README file would be stored at
the path "dino/README" instead of just "/README".

Import project files directly into the top-level directory, as expected.
Adjust test expectations accordingly.