corrected bug discovered by tf 1.3
corrected bug discovered by tf 1.3

juliakreutzer/bandit-neuralmonkey,juliakreutzer/bandit-neuralmonkey,juliakreutzer/bandit-neuralmonkey,bastings/neuralmonkey,ufal/neuralmonkey,juliakreutzer/bandit-neuralmonkey,ufal/neuralmonkey,ufal/neuralmonkey,juliakreutzer/bandit-neuralmonkey,bastings/neuralmonkey,ufal/neuralmonkey,bastings/neuralmonkey,bastings/neuralmonkey,bastings/neuralmonkey,ufal/neuralmonkey