Deprecated Padding Attribute in Pooling

[wschin]

When converting models from Core ML, we should calculate the padding amounts and create a ONNX Pad operator to replace the use of deprecated attributes (e.g., SAME_LOWER).

For example of a correct solution, we calculate the padding amounts explicitly for Core ML's IncludeLastPixel padding model in Pooling. Then, a ONNX Pad is created to replace that padding in Pool.