Examples reorg (#11350)

* Base move

* Examples reorganization

* Update references

* Put back test data

* Move conftest

* More fixes

* Move test data to test fixtures

* Update path

* Apply suggestions from code review

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

* Address review comments and clean

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

examples/tensorflow/README.md

@@ -0,0 +1,42 @@
+<!---
+Copyright 2020 The HuggingFace Team. All rights reserved.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+-->
+
+# Examples
+
+This folder contains actively maintained examples of use of 🤗 Transformers using the TensorFlow backend, organized along NLP tasks. It is under construction so we thank you for your patience!
+
+## The Big Table of Tasks
+
+Here is the list of all our examples:
+- with information on whether they are **built on top of `Keras`** (if not, they still work, they might
+  just lack some features),
+- whether or not they leverage the [🤗 Datasets](https://github.com/huggingface/datasets) library.
+- links to **Colab notebooks** to walk through the scripts and run them easily,
+<!--
+Coming soon!
+- links to **Cloud deployments** to be able to deploy large-scale trainings in the Cloud with little to no setup.
+-->
+
+| Task | Example datasets | Keras support | 🤗 Datasets | Colab
+|---|---|:---:|:---:|:---:|
+| **`language-modeling`** | WikiText-2 | - | - | -
+| [**`multiple-choice`**](https://github.com/huggingface/transformers/tree/master/examples/tensorflow/multiple-choice) | SWAG | - | - | -
+| [**`question-answering`**](https://github.com/huggingface/transformers/tree/master/examples/tensorflow/question-answering) | SQuAD | - | - | -
+| **`summarization`** | XSum | - | -  | -
+| [**`text-classification`**](https://github.com/huggingface/transformers/tree/master/examples/tensorflow/text-classification) | GLUE | - | - | -
+| **`text-generation`** | n/a | - | n/a | -
+| **`token-classification`** | CoNLL NER | - | - | - 
+| **`translation`** | WMT | -  | - | -
+