message: Document how to read associated files from the zip format
diff: @@ -472,15 +472,39 @@ public QuantizationParams getoutputTensorQuantizationParams(int inputIndex);
  public int[] getoutputTensorShape(int inputIndex);
  ```
  -You can also read associated files through their names with the
  -`getAssociatedFile` method:
  -
  -```java
  -public InputStream getAssociatedFile(String fileName);
  -```
  -
  Though the
  [TensorFlow Lite model schema](https://github.com/tensorflow/tensorflow/blob/aa7ff6aa28977826e7acae379e82da22482b2bf2/tensorflow/lite/schema/schema.fbs#L1075)
  supports multiple subgraphs, the TFLite Interpreter currently only supports a
  single subgraph. Therefore, `MetadataExtractor` omits subgraph index as an input
  argument in its methods.
  +
  +## Read the associated files from models
  +
  +The TensorFlow Lite model with metadata and associated files is essentially a
  +zip file that can be unpacked with common zip tools to get the associated files.
  +For example, you can unzip
  +[mobilenet_v1_0.75_160_quantized](https://tfhub.dev/tensorflow/lite-model/mobilenet_v1_0.75_160_quantized/1/metadata/1)
  +and extract the label file in the model as follows:
  +
  +```sh
  +$ unzip mobilenet_v1_0.75_160_quantized_1_metadata_1.tflite
  +Archive: mobilenet_v1_0.75_160_quantized_1_metadata_1.tflite
  + extracting: labels.txt
  +```
  +
  +You can also read associated files through the Metadata Extractor library.
  +
  +In Java, pass the file name into the `MetadataExtractor.getAssociatedFile`
  +method:
  +
  +```java
  +public InputStream getAssociatedFile(String fileName);
  +```
  +
  +Similarily, in C++, this can be done with the method,
  +`ModelMetadataExtractor::GetAssociatedFile`:
  +
  +```c++
  +tflite::support::StatusOr<absl::string_view> GetAssociatedFile(
  + const std::string& filename) const;
  +```
  