Make Ahab list installed packages

[fitzoh]

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• What are you trying to do?
  Instead of passing in a list of packages, have Ahab figure them out for me

• What feature or behavior is this required for?
  To allow me to be lazy

• How could we solve this issue? (Not knowing is okay!)
  Have Ahab call the appropriate apt/yum commands itself

• Anything else?
  nah

cc @bhamail / @DarthHater / @ken-duck