These truthfully should be up to users to maintain, as
trying to add everyones editor of choice config directories
here isn't ideal.

This additionally adds a section in contributing on the new stance.

This was referenced

katiewasnothere added a commit to apple/container that referenced this pull request

These should be up to users to maintain, as trying to add everyones
editor of choice config directories here isn't ideal.

Matches apple/containerization#106

Signed-off-by: Kathryn Baldauf <k_baldauf@apple.com>