Reorganize examples (#9010)

* Reorganize example folder

* Continue reorganization

* Change requirements for tests

* Final cleanup

* Finish regroup with tests all passing

* Copyright

* Requirements and readme

* Make a full link for the documentation

* Address review comments

* Apply suggestions from code review

Co-authored-by: Lysandre Debut <lysandre@huggingface.co>

* Add symlink

* Reorg again

* Apply suggestions from code review

Co-authored-by: Thomas Wolf <thomwolf@users.noreply.github.com>

* Adapt title

* Update to new strucutre

* Remove test

* Update READMEs

Co-authored-by: Lysandre Debut <lysandre@huggingface.co>
Co-authored-by: Thomas Wolf <thomwolf@users.noreply.github.com>

examples/research_projects/seq2seq-distillation/finetune_bart_tiny.sh

@@ -0,0 +1,32 @@
+# Script for verifying that run_bart_sum can be invoked from its directory
+
+# Get tiny dataset with cnn_dm format (4 examples for train, val, test)
+wget https://cdn-datasets.huggingface.co/summarization/cnn_tiny.tgz
+tar -xzvf cnn_tiny.tgz
+rm cnn_tiny.tgz
+
+export OUTPUT_DIR_NAME=bart_utest_output
+export CURRENT_DIR=${PWD}
+export OUTPUT_DIR=${CURRENT_DIR}/${OUTPUT_DIR_NAME}
+
+# Make output directory if it doesn't exist
+mkdir -p $OUTPUT_DIR
+
+# Add parent directory to python path to access lightning_base.py and testing_utils.py
+export PYTHONPATH="../":"${PYTHONPATH}"
+python finetune.py \
+--data_dir=cnn_tiny/ \
+--model_name_or_path=sshleifer/bart-tiny-random \
+--learning_rate=3e-5 \
+--train_batch_size=2 \
+--eval_batch_size=2 \
+--output_dir=$OUTPUT_DIR \
+--num_train_epochs=1  \
+--gpus=0 \
+--do_train "$@"
+
+rm -rf cnn_tiny
+rm -rf $OUTPUT_DIR
+
+
+