Closes#1170.
This branch adds a `-o wide` (or `--output wide`) flag to the Tap CLI.
Passing this flag adds `src_res` and `dst_res` elements to the Tap
output, as described in #1170. These use the metadata labels in the tap
event to describe what Kubernetes resource the source and destination
peers belong to, based on what resource type is being tapped, and fall
back to pods if either peer is not a member of the specified resource
type.
In addition, when the resource type is not `namespace`, `src_ns` and
`dst_ns` elements are added, which show what namespaces the the source
and destination peers are in. For peers which are not in the Kubernetes
cluster, none of these labels are displayed.
The source metadata added in #1434 is used to populate the `src_res` and
`src_ns` fields.
Also, this branch includes some refactoring to how tap output is
formatted.
Signed-off-by: Eliza Weisman <eliza@buoyant.io>
Eliza Weisman