Volunteer Roster should include section for unassigned volunteers

For Volunteer Opportunities with no specific roles defined, there is nothing to assign a volunteer to. On these opportunities, the roster says there are no volunteers assigned to this project. While technically correct, it may imply to the user that no one has signed up for the project.

Another use case may be all my defined roles are full and a volunteer still signs up for "Any role." Since all my roles are full, I have nothing to assign her to. When she shows up at the event, she's not on the roster and, woops, I only bought lunch for the twelve volunteers on the roster.

Lastly, for the example of a river cleanup, I may have an event that would not need roles at all. Everyone is cleaning. Creating a role of "Cleaning the River" would be redundant and then assigning everyone who has signed up to that role would be extra work with little benefit except to make the volunteer roster work.

Another use case might be if a volunteer or two does not show up for their assigned role, but my roster shows that Judy has signed up and volunteered to do anything so she can just fill in when she gets here.

An additional section on the roster that lists "Unassigned" volunteers should take care of this quite nicely and would work if there are defined roles or not.