修改不选择项目时的<<NULL>>为 NO PROJECT

app/helpers/homework_attach_helper.rb

@@ -60,7 +60,7 @@ module HomeworkAttachHelper
     memberships = User.current.memberships.all(:conditions => cond)
     projects = memberships.map(&:project)
     not_have_project = []
-    not_have_project << "<<NULL>>"
+    not_have_project << "NO PROJECT"
     not_have_project << 0
     type = []
     type << not_have_project