Fix typo.
(Ouch, how did that get in? My local environment must have pulled luarocks.cfg from somewhere else. Need to check that.)
Since we're using our own mkdir, use mkdir -p to create subdirectories.
Should suffice for #140 but needs testing.
Merge branch 'master' of https://github.com/keplerproject/luarocks into move_win_binaries
normalize directory before creating a directory path. Fixes #140