fix minor assignment.open? missing ? bug in assignment_presenter.rb
fix minor assignment.open? missing ? bug in assignment_presenter.rb

mkoon/gradecraft-development,mkoon/gradecraft-development,UM-USElab/gradecraft-development,UM-USElab/gradecraft-development,mkoon/gradecraft-development,UM-USElab/gradecraft-development,UM-USElab/gradecraft-development