Introducing cgroups details

This release is a big step forward as it introduces two new ways that you can explore namespaces and cgroups:

• a sort of reverse lookup: cinf --pid 9422 lists all the namespaces the process with PID 9422 is in
• a cgroups details query: cinf --cgroup 5:9422 lists consumption details of the cgroup of the hierarchy ID 5 (which happens to be mapped to memory on my test system) for the process with PID 9422

Other things done are a consolidation of the CLI arguments (it used to be --namespace as the default, implicit argument) and some more docs around cgroups.