docs: add guide for adding a new dataset and a new task (#628)

* Add guide for adding a new dataset and a new task

* Format Markdown files

Author: anhappdev

docs/adding-new-dataset-and-task.md

@@ -0,0 +1,16 @@
+# Adding a new dataset and a new task
+
+1. Add code for the new dataset [1] (e.g. `snu_sr.{cc,h}`) to `flutter/cpp/datasets` and corresponding building rule(s) in `flutter/cpp/datasets/BUILD`.
+2. Add corresponding code to `flutter/cpp/binary/main.cc` so we can test the dataset with CLI.
+3. Add a new task specific `benchmark_setting` to backends so that accelerators could be used. E.g. adding a new setting to TFLite backend by modifying `mobile_back_tflite/cpp/backend_tflite/tflite_settings_android.h`, for an example see [d23d16c](https://github.com/mlcommons/mobile_app_open/commit/d23d16c6cec110786379fa8d3a5e2b49e1b80b0e)
+4. Add a new task to the `flutter/assets/tasks.pbtxt` file.
+5. Add a new task to Flutter code part.
+6. Add an integration test for the new task.
+
+See the [PR #574](https://github.com/mlcommons/mobile_app_open/pull/574) for an example how to add the new SNUSR dataset.
+
+See the [PR #608](https://github.com/mlcommons/mobile_app_open/pull/608) for an example how to add the new super resolution task.
+
+See the [issue #595](https://github.com/mlcommons/mobile_app_open/issues/595) for a complete discussion how we added the new super resolution task.
+
+[1] What does "a dataset" mean? A dataset here is to implement LoadGen's Query Sample Library (QSL). Actually, we can share some common methods and the MLPerfDriver uses interface defined in `flutter/cpp/dataset.h`, all the datasets in `flutter/cpp/datasets/` now inherit the `mlperf::mobile::Dataset`.

docs/readme.md

@@ -15,5 +15,6 @@ Refer to the [root README file](../README.md) for general overview of the repo.
 * [Build and Run the app](./build-and-run.md)
 * [Adding support for a new custom backend](./adding-custom-backend.md)
 * [Using custom benchmark configuration](./custom-tasks.md)
+* [Adding a new dataset and a new task](./adding-new-dataset-and-task.md)
 * [Working with Firebase](./firebase.md)
 * [Formal result specification](./result-spec.md)