Add Mageia-3 templates, based on existing mageia-2 templates.
Add link to documentation of auto_inst.cfg.
Remove config options which are not required or even discuraged.
Reduce installed packages to the bare minimum plus urpmi and sshd.

This not even includes initsripts and chkconfig, as these are not longer
required by the Mageia-3 base-system. A kernel containig the
vboxadditions is installed.
Use cleartext passwd instead of crypted one.

This makes it easier zu maintain the file. E.g. for the case
the crypto-algorithm for the password changes.
Cleanup white-space.
Cleanup white-space.
Reorder stuff.
Make definitions.rb more modular.
Reduce postInstall commands in auto_inst.cfg to the bare requirements.

- Disable shorewall instead of deleting it.
- Keep 'kernel-*-latest' as vboxadditions are coming from
  official Mageia packages.
Split up postinstall.sh into smaller scripts.
Rename definition according to naming scheme.
Clean ~root/drakx files (created on installation).
Remove traces of mac address from all ifcfg-* files.
Change local name of iso-file: include name, version, arch.
Do not include vagrant-key, ruby and puppet by default.
Add Mageia-4-server-x86_64-minimal.

Based in Mageia-4-server-x86_64-minimal. Changes are:
- Name of network-device has changed to 'enp0s3'.
- /etc/udev/rules.d/70-persistent-net.rules no longer
  exists.
Update documentation.