Include a features.sh script in the full/beta images

[tjwatson]

Currently the features.sh script is only in the kernel feature. This has two inconveniences

1. When switching the FROM image from kernel to full one must always remember to remove any calls to features.sh from their Dockerfile
2. If a user has created product extensions they cannot use the features.sh script to install them on the full image like the would when using the kernel image.