Update rmi.md

[djgoosen]

- What I did

- How I did it

- How to verify it

- Description for the changelog

- A picture of a cute animal (not mandatory but encouraged)

[GordonTheTurtle]

Please sign your commits following these rules:
https://github.com/moby/moby/blob/master/CONTRIBUTING.md#sign-your-work
The easiest way to do this is to amend the last commit:

$ git clone -b "patch-1" git@github.com:djgoosen/cli.git somewhere
$ cd somewhere
$ git commit --amend -s --no-edit
$ git push -f

Amending updates the existing PR. You DO NOT need to open a new one.

[codecov-io]

Codecov Report

Merging #580 into master will decrease coverage by 0.03%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #580      +/-   ##
==========================================
- Coverage   49.41%   49.38%   -0.04%     
==========================================
  Files         208      208              
  Lines       17186    17178       -8     
==========================================
- Hits         8493     8483      -10     
- Misses       8261     8262       +1     
- Partials      432      433       +1

[mdlinville]

Please sign your commit and use a more informative title for your pull request. Thanks!

[thaJeztah]

LGTM, thanks!