Document: EAP images are tied to IPv4 address

Configuration of EAP 7 images are tied to IPv4 address and do not require any changes if started on Openshift on IPv4 network.

However If deployed to Openshift 4 which is on IPv6 network then start of such an image will fail. Changes to configuration of such an image is needed to be able start and bind to IPv6 addresses. Generally those changes are described in:
https://access.redhat.com/documentation/en-us/red_hat_jboss_enterprise_application_platform/7.4/html-single/configuration_guide/index#ipv6_addresses

What needs to be documented:

• EAP 7 images are by default configured to be run on Openshift on IPv4 network. Even though this information can be derived from used JAVA_OPTS=-Djava.net.preferIPv4Stack=true it's quite cryptic and it should be exlicitly noted.
• Information how to reconfigure EAP image with IPv6 address should be provided. For the start we should link: https://access.redhat.com/documentation/en-us/red_hat_jboss_enterprise_application_platform/7.4/html-single/configuration_guide/index#ipv6_addresses . Later on we might provide CLI script and configuration for environment variables (like JAVA_OPTS) which are needed for the pod to start.

This should be documented into "Getting Started with JBoss EAP for OpenShift Container Platform guide":
https://access.redhat.com/documentation/en-us/red_hat_jboss_enterprise_application_platform/7.4/html-single/getting_started_with_jboss_eap_for_openshift_container_platform/index