Ability to exclude additions

[zendesk-slowery23]

Is there a way to exclude additions in the report? It would be a useful feature to be able to exclude additions to focus on changed and deleted attributes as those are mostly likely to cause problems if engineers are following good release practices.

As an example, if I had this file as the "from"

apiVersion: apps/v1
kind: Deployment
metadata:
  name: foo
  annotations:
    bar: bar

And this file as the "to"

apiVersion: apps/v1
kind: Deployment
metadata:
  name: foo
  annotations:
    bar: bar2
    baz: baz

Running dyff with some sort of --exclude-additions flag to have the report only show

     _        __  __
   _| |_   _ / _|/ _|  between one.yml
 / _' | | | | |_| |_       and two.yml
| (_| | |_| |  _|  _|
 \__,_|\__, |_| |_|   returned one differences
        |___/

metadata.annotations.bar
  ± value change
    - bar
    + bar2