add render related flags/options

[bergerx]

We can let users choose what t be displayed. Here are some flags that may be implemented:

• include owners: render owner objects (this is the current default behavior)
• include dependents: reverse of owners
• include events
• include matching services
• include matching ingresses
• include app information (e.g helm)
• cascade render options: apply the same render options when rendering a related object
• shallow: render only the object itself doesn't query kubernetes API for other resources than the immediate resource, would likely disable most includes

[bergerx]

We also need to properly model the cmd struct, here is a good example: https://github.com/knight42/kubectl-blame/blob/master/cmd/blame.go