I would suggest to look at Tuleap Trackers[1]. The tracking system is flexible enough to allow you to define your own layout for requirements and define a set of elements to help you categorize them.
I'm from the development team and we are using it for our very own requirement tracker (in an Agile way but that's not mandatory to follow an agile methodology to use it). You can have a look at some of your requirements / user stories:
* https://tuleap.net/plugins/tracker/?aid=7923 you can see how to structure the text and at the bottom the discussion and the modifications done by each user. * https://tuleap.net/plugins/tracker/?aid=8262 same with another topic.
The most important character of "an issue" or "a requirement" it is that it is a unit of work that can be "done", "in progress", or "not done". Throughout the life of the project, there are going to be negotiations between people about what exactly is done and how requirements will change, and those kind of systems are designed for that and capture not only the changes but also some of the semantics.
Some issue tracker may have (6) AND (7) built in. Otherwise you may need to make some reports.