Add revoke.sh

Dockerfile

@@ -12,6 +12,7 @@ RUN set -x \
            && yum install openvpn stonevpn -y \
            && chmod +x /tmp/docker-entrypoint.sh \
            && chmod +x /tmp/keygen.sh \
+           && chmod +x /tmp/revoke.sh \
            && chmod 400 /etc/openvpn/keys/*.key \
            && chmod 440 /etc/openvpn/keys/*.crt \
            && yum install -y https://centos7.iuscommunity.org/ius-release.rpm \