Added prereq installation links per DDF customer request

You have installed the following required software:

Docker - For installation instructions, see Get Docker.
Cekit version 3.2 - For installation instructions, see Installation.
The following libraries and extensions for Cekit. For more information, see Dependencies:
odcs-client, provided by the python3-odcs-client package or similar package
docker, provided by the python3-docker package or similar package
docker-squash, provided by the python3-docker-squash package or similar package
behave, provided by the python3-behave package or similar package
s2i, provided by the source-to-image package or similar package

Original jira: https://issues.redhat.com/browse/BXMSDOC-6430
Rendered output: http://file.rdu.redhat.com/~mhaglund/BXMSDOC-6430/#externaldb-build-proc_openshift-authoring
Pull request: https://github.com/michelehaglund/kie-docs/pull/162