CreateControllerUsers accepts a cluster config, and cfgVars and creates controller users accordingly.

CreateUser creates a system user with either `adduser` or `useradd` command.

CreateControllerUsers accepts a cluster config, and cfgVars and creates controller users accordingly.

DeleteUser deletes system users with either `deluser` or `userdel` command.

EnsureService installs the k0s service, per the given arguments, and the detected platform.

EnsureUser checks if a user exists, and creates it, if it doesn't TODO: we should also consider modifying the user, if the user exists, but with wrong settings.

This function attempts to find out the host role, by staged binaries.

GetSysInit returns the sys init platform name, and the stub file path for a system.