Categories now required when creating topics

Over in another discussion we started to come to the conclusion (see quotes below) that members should be required to select a category when posting.

This helps keep the topics organised (so that people can track and mute to their taste).

I’ve enabled this, and as part of this change I needed to create a new category to hold all existing uncategorised topics. Through lack of imagination I’ve called it “Other” for now, but open to suggestions!