Better infer_shape test for Softmax, SoftmaxWithBias, SoftmaxGrad, CrossentropySoftmaxArgmax1HotWithBias, ConvOp, Conv3D, ConvTransp3D, ConvGrad3D
Added and tested infer_shape for CrossentropySoftmax1HotWithBiasDx,Prepend_scalar_constant_to_each_row and Prepend_scalar_to_each_row, CrossentropyCategorical1HotGrad

Added disabled CrossentropyCategorical1Hot.infer_shape, see gh-788