Be more explicit about system requirements

[nwneisen]

We currently have the following page that describes the system requirements for the mke-operator. i.e. the cluster nodes

The information is correct and this page is talking about the cluster so this is okay but we should update the mkectl install page to mention what the system requirements are. Especially since they are different from the nodes.

mkectl is currently built for

os	arch
linux	64 bit and arm
mac	64 bit and apple silicon (arm)
windows	64 bit and arm

We should make the decision of what distros to support for linux also. While the binary doesn't use any shared libraries and should work everywhere (probably not really), the install script expects some tools to be installed that aren't on some lightweight distros. Or they could be a different name. We can fix some of these but overall we should draw a line for what we will support.

[sergeymirantis]

Just a small comment as I go through this.. since we are "pulling" in dependencies (k0sctl, kubectl) - is there a way to automatically detect other dependencies like "file" command and such? Just to eliviate the human factor from pre-reqs?