Fixed the xor-batch-lookup example
Fixed the xor-batch-lookup example

cherryc/dynet,dhgarrette/cnn,Peilun-Li/dynet,Abasyoni/dynet,kamigaito/cnn,cherryc/dynet,dhgarrette/cnn,Abasyoni/dynet,kamigaito/cnn,cherryc/dynet,mitchellstern/dynet,dhgarrette/cnn,mitchellstern/dynet,Peilun-Li/dynet,Abasyoni/dynet,Peilun-Li/dynet