Refactor the whole binary, a lot of changes in one commit I know, but I just hacked on this and modified everything I thought was messy or could be done better.

Fix boilerplates, comments in the code and make the output of kubeadm more user-friendly
Start using HostPKIPath and KubernetesDir everywhere in the code, so they can be changed for real
More robust kubeadm reset code now.
Removed old glog-things from app.Run()
Renamed /etc/kubernetes/cloud-config.json to /etc/kubernetes/cloud-config since it shouldn't be a json file
Simplification of the code
Less verbose output from master/pki.go
Cleaned up dead code

Start a small logging/output framework:
 - fmt.Println("[the-stage-here] Capital first letter of this message. Tell the user what the current state is")
 - fmt.Printf("[the-stage-here] Capital first letter. Maybe a [%v] in the end if an error should be displayed. Always ends with \n")
 - fmt.Errorf("Never starts with []. Includes a short error message plus the underlying error in [%v]. Never ends with \n")