During operations with `linkerd stat` sometimes it's not clear the actual
pod status.
This commit introduces a method, to the `k8s`package, getting the pod status,
based on [`kubectl` logic](33a3e325f7/pkg/printers/internalversion/printers.go (L558-L640))
to expose the `STATUS` column for pods . Also, it changes the stat command
on the` cli` package adding a column when the resource type is a Pod.
Fixes#1967
Signed-off-by: Jonathan Juares Beber <jonathanbeber@gmail.com>