WIP: start on changing to just remove players from team, instead of active/inactive
better eager loading. was previously using joins, which automatically removes blank users... but I feel that is more subtle than just rejecting blank users outright
also destroy practice sessions for destroyed team_members
more clear delete button instructions
remove old comments, cache the player_status
only show save settings button for captains. members can only remove themselves.
fix up welcome emails, fix bugs with team creation