avoid code duplication with local cmake modules; fixes #32

the directory for downloaded modules is renamed from modules/ to downloaded/

.gitignore

@@ -4,9 +4,9 @@ __pycache__/
 # generated by unit tests
 test/*/CMakeLists.txt
 test/*/build*/
-test/*/cmake/update.py*
+test/*/cmake/update.py
 test/*/cmake/lib/
-test/*/cmake/modules/
+test/*/cmake/downloaded/
 test/*/setup.py
 
 # generated by doc/extract_rst.py