Navigation dot for project issue boards
Design

- Show the blue dot (and the pop up UI) in the project navigation (as in the mockup) of _any_ project, when certain conditions are met.
- All of these conditions must be met for the blue dot to be shown:
- You are logged in.
- You have not previously dismissed it in any project ever in your lifetime as yourself (as a unique user).
- To satisfy the above requirement, the system needs to store the user's dismissal in the database.
- This is unchanged across GitLab version changes / deployments. If GitLab is deployed onto the system, it should not change the dismissal status in the database.
- Note that this means if a user has dismissed it once in one project nav, it is forever dismissed in all project navs they ever visit in the future, including projects that have not been created yet.
- This applies both to the project issue board(s) for both CE and EE.
- This does _not_ apply to the group boards.
- This does not apply to the fly out menus.