unix rewrite

[efrecon]

A large part of the unix module is based on executing processes on the (remote) machine to collect information. At the time of writing, procfs is being integrated to provide a proper hardware inventory whenever running against minimal OSes such as Rancher. With the venue of procfs integration, most of the original unix module can be rewritten on top in order to minimise code duplication, improve integration and reduce resource consumption through minimising the number of processes being fired.