allow a "tester" to create a game master if none exists

[timflutre]

This means that the "Admin" tab should be available to the "tester" only if no "game master" exists.

[juliendiot42]

Just for information, the case where no "game master" exists shouldn't happen :

The "admin" breeder (with "game master" status) is created with with the game installation (when the database is created) and it is impossible to delete this breeder in the game (in admin tab):

See file server_admin.R (develop branch) lines 77 to 81:

    }else if (input$delBreederName=="admin") {
        progressDelBreeder$set(value = 0,
                               message = "Deleting breeder",
                               detail = "Sorry, admin can't be deleted.")
    }

Unless someone delete the "admin" breeder directly in the database, this breeder should always be here.

[timflutre]

The latest version of the setup.Rmd allows not to create any "game master" player. In contrast, a "tester" player is always created. The goal is to allow external people to download the code and run the game without any password, using the "tester" player. Then, if they want, they can create a "game master" player. The code of the game hence should allow that.

[timflutre]

As discussed with Julien, this task isn't relevant anymore.