Make '--win-sys env' default

Make '--win-sys env' default

Without this patch, the default path used by OpenVPN is hard coded
to C:\WINDOWS.  As users might install Windows in a different directory,
this approach will cause OpenVPN to malfunction in some configurations.

OpenVPN have supported using the system path, by adding --win-sys env.
This patch removes the hard coded approach and uses the --win-sys env
approach by default instead.

Trac-ticket: 66
URL: http://thread.gmane.org/gmane.network.openvpn.user/32508
Signed-off-by: David Sommerseth <davids@redhat.com>
Tested-by: Samuli Seppänen <samuli@openvpn.net>
Acked-by: Gert Doering <gert@greenie.muc.de>