use correct location for upbind config files, and allow override via environment variable
use correct location for upbind config files, and allow override via environment variable

git-svn-id: cedaea21d87b8e7ca64e45ff9f22dc59bd4b9fcf@4255 25043fe6-1616-0410-a82d-ba8f324cfe61

davidfraser/upbind,davidfraser/upbind