Fix an error when shutil.copyfile() was used with path.basename() instead full path; use local copyfile() function to update file permissions
Add a unit test for --always-copy option
4 changes to `test_always_copy_option`:
1) let it run for windows;  should be harmless
2) confirm files and dirs are not links
3) create the tmp venvs in a *new* directory
4) if a symlink is found, report what it's linked to
1) when copying, symlink=False has to be passed to copyfile
2) copyfile(symlink=True) is a suitable replacement for os.symlink
Merge pull request #511 from qwcode/always-copy

Fix --always-copy