This adds some comments to the sample images to describe what
is going on.

It also fixes up a few minor details:
 * Fix name to match filenames
 * Drop unused variables
 * Rename qmcontainer to qm-container to match other examples

We also add two new examples:
 * apps.mpp.yml - Installs sample-apps in the rootfs
 * qm-apps.mpp.yml Installs sample-apps in the QM, but not containerized

This means we have for the rootfs these demos:
 * minimal - nothing
 * apps - sample-apps as rpms
 * container - sample-apps as container
 * qm-minimal - nothing, with qm
 * qm-apps - sample-apps as rpms in qm
 * qm-container - sample-apps as container in qm