Consistency between carvel tools for filtering

**Describe the problem/challenge you have**
Carvel tool users have to learn filtering capabilities in some of the tools in the suite. The most prominent one is `ytt` where users have to learn filtering in the matchers. When a user goes to kapp, he finds a plethora of options to filter the resources which:
- are not aligned with the ones in `ytt`
- have like a gazillion different cli options to filter by many different fields

This is the output from the CLI help:

```
Resource Filter Flags:
--filter string Set filter (example: {"and":[{"not":{"resource":{"kinds":["foo%"]}}},{"resource":{"kinds":["!foo"]}}]})
--filter-age string Set age filter (example: 5m, 500h+, 10m-)
--filter-kind strings Set kinds filter (example: Pod) (can repeat)
--filter-kind-name strings Set kind-name filter (example: Pod/controller) (can repeat)
--filter-kind-ns strings Set kind-namespace filter (example: Pod/, Pod/knative-serving) (can repeat)
--filter-kind-ns-name strings Set kind-namespace-name filter (example: Deployment/knative-serving/controller) (can repeat)
--filter-name strings Set name filter (example: controller) (can repeat)
--filter-ns strings Set namespace filter (example: knative-serving) (can repeat)
```

**Describe the solution you'd like**
What I would expect is consistency between the tools so that a user that learns how to use one tool can leverage that expertise on the following one.

I would expect something like:
```
Resource Filter Flags:
--filter string Set filter (example: {"metadata":{"namespace":"foo"}})
```

cc/ @GrahamDumpleton

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