Optimise the import of scripts into the kickstart file

[hferentschik]

Currently we have something like:

cat > cert-gen.sh.base64 << EOF
${cert_gen}
EOF
base64 -d < cert-gen.sh.base64 > cert-gen.sh

This could be further reduced to

${cert_gen}
chmod +x cert-gen.sh
mv cert-gen.sh /opt

where the boilerplate code is generated as well. In the end it would also expand to something like

cat > cert-gen.sh.base64 << EOF
<base 64 encoded script>
EOF
base64 -d < cert-gen.sh.base64 > cert-gen.sh

[coolbrg]

@hferentschik , we have some recent changes related to cert-gen here https://github.com/minishift/minishift-centos-iso/blob/master/centos-7.template#L105-L112.

Do we still need optimization?

[gbraad]

This doesn't change the need for the optimization. However, the Fedora livecd creator talks about copying files in the liveroot filesystem. Reading it felt like what we need however I have never been able to make this work for livecd creator for CentOS... ? Maybe it doesnt do what I expect. It mafe no difference using %post or %post -no-chroot