add option --management-query-proxy

add option --management-query-proxy

Make openvpn query for proxy information through the
management interface. This allows GUIs to provide (automatically
detected) proxy information on a per connection basis.

This new option supersedes the undocumented --http-proxy-fallback
option and puts the responsibilty for HTTP proxy fallback handling
to the GUI caring for such.

Signed-off-by: Heiko Hund <heiko.hund@sophos.com>
Reviewed-by: James Yonan <james@openvpn.net>
Message-Id: 1342009010-9735-1-git-send-email-heiko.hund@sophos.com
URL: http://article.gmane.org/gmane.network.openvpn.devel/6841
Signed-off-by: David Sommerseth <dazo@users.sourceforge.net>