added tests for add() method.
added tests for add() method.

justinchu17/ilios,justinchu17/ilios,Trott/ilios,ilios/ilios,dartajax/ilios,stopfstedt/ilios,Trott/ilios,thecoolestguy/ilios,thecoolestguy/ilios,stopfstedt/ilios,ilios/ilios,justinchu17/ilios,justinchu17/ilios,dartajax/ilios