When cancelling a download, ensure file is closed before unlinking
When cancelling a download, ensure file is closed before unlinking

Otherwise, Windows will fail with:

  Unix.Unix_error(Unix.EACCES, "unlink", "...")

Also, just log a warning if we still can't delete the temporary file.

DarkGreising/0install,HoMeCracKeR/0install,bastianeicher/0install,pombreda/0install,bartbes/0install,bhilton/0install,0install/0install,bartbes/0install,gasche/0install,jaychoo/0install,DarkGreising/0install,gasche/0install,gfxmonk/0install,0install/0install,bhilton/0install,DarkGreising/0install,pombreda/0install,bartbes/0install,bastianeicher/0install,0install/0install,gasche/0install,pombreda/0install,jaychoo/0install,HoMeCracKeR/0install,gasche/0install,bhilton/0install,gfxmonk/0install,gfxmonk/0install,jaychoo/0install,HoMeCracKeR/0install,bastianeicher/0install