In load roster from QBJ registration tab, allow typing in extra players

[hftf]

Use case: tournament director provides a roster file, but another player has joined a team late. Adding the player to the team requires a separate workflow but ideally it should be possible to enter more players in the same workflow once selecting a team from the roster dropdown.

[alopezlago]

This is a good idea, though potentially a little complex to implement, so I likely won't get around to it for a while.