mbleigh/acts-as-taggable-on — pull request #346 by cwoodcox (2013-04-18 19:20:12+00:00)
Title: only use attr_accessible if it's supported

Rails 4 doesn't define the ActiveModel::MassAssignmentSecurity constant, but
there is a gem that allows it to be used. The models will now only try to use
the functionality if the constant is defined

fixes #334