Allow comments to be organized into groups

[501st-alpha1]

With a large number of auto comments (which can happen if you e.g. import from this repo), it can be hard to navigate to quickly find the right one. One option to make the correct comment easier to find was suggested in #113.

I'd like to propose another option: it would be nice to have the ability to sort the auto comments into groups, maybe even with sub groups.

As an example, I could have a group called Not An Answer, with sub-groups for whether the answer should instead be an upvote, comment, or edit. In those sub-groups could be auto-comments for specific situations (should be comment on answer, should be comment on question, etc.).