Merge pull request #5772 from ChihebTrabelsi/add_conv2d_transpose2doc

doc/library/tensor/nnet/conv.txt

@@ -219,6 +219,7 @@ TODO: Give examples on how to use these things! They are pretty complicated.
       It flip the kernel.
 
 .. autofunction:: theano.tensor.nnet.conv2d
+.. autofunction:: theano.tensor.nnet.conv2d_transpose
 .. autofunction:: theano.tensor.nnet.conv3d
 .. autofunction:: theano.sandbox.cuda.fftconv.conv2d_fft
 .. autofunction:: theano.tensor.nnet.Conv3D.conv3D