No Call to Action button on empty issue tracker when group has no projects

There is no Call to Action on the empty issue tracker. I can't tell if that is because the feature is not enabled or because I haven't added an issue yet.
After looking further, I realized that this is happening because the group has no projects. We should update the Call to Action to include text that explains this.
> ### The Issue Tracker is the place to add things that need to be improved or solved in a project
>
> Issues are created within projects. Currently [group name] has no projects. In order to add issues to the issue tracker, a project must be created.
>
> [Create project to add issues]
(After creating the project, we should automatically link to the new issue page)
issue