Dataset v2.0 (#461)

Co-authored-by: Remi <remi.cadene@huggingface.co>

examples/7_get_started_with_real_robot.md

@@ -778,7 +778,6 @@ Now run this to record 2 episodes:
 python lerobot/scripts/control_robot.py record \
   --robot-path lerobot/configs/robot/koch.yaml \
   --fps 30 \
-  --root data \
   --repo-id ${HF_USER}/koch_test \
   --tags tutorial \
   --warmup-time-s 5 \
@@ -787,7 +786,7 @@ python lerobot/scripts/control_robot.py record \
   --num-episodes 2
 ```
 
-This will write your dataset locally to `{root}/{repo-id}` (e.g. `data/cadene/koch_test`) and push it on the hub at `https://huggingface.co/datasets/{HF_USER}/{repo-id}`. Your dataset will be automatically tagged with `LeRobot` for the community to find it easily, and you can also add custom tags (in this case `tutorial` for example).
+This will write your dataset locally to `~/.cache/huggingface/lerobot/{repo-id}` (e.g. `data/cadene/koch_test`) and push it on the hub at `https://huggingface.co/datasets/{HF_USER}/{repo-id}`. Your dataset will be automatically tagged with `LeRobot` for the community to find it easily, and you can also add custom tags (in this case `tutorial` for example).
 
 You can look for other LeRobot datasets on the hub by searching for `LeRobot` tags: https://huggingface.co/datasets?other=LeRobot
 
@@ -840,7 +839,6 @@ In the coming months, we plan to release a foundational model for robotics. We a
 You can visualize your dataset by running:
 ```bash
 python lerobot/scripts/visualize_dataset_html.py \
-  --root data \
   --repo-id ${HF_USER}/koch_test
 ```
 
@@ -858,7 +856,6 @@ To replay the first episode of the dataset you just recorded, run the following
 python lerobot/scripts/control_robot.py replay \
   --robot-path lerobot/configs/robot/koch.yaml \
   --fps 30 \
-  --root data \
   --repo-id ${HF_USER}/koch_test \
   --episode 0
 ```
@@ -871,7 +868,7 @@ Your robot should replicate movements similar to those you recorded. For example
 
 To train a policy to control your robot, use the [`python lerobot/scripts/train.py`](../lerobot/scripts/train.py) script. A few arguments are required. Here is an example command:
 ```bash
-DATA_DIR=data python lerobot/scripts/train.py \
+python lerobot/scripts/train.py \
   dataset_repo_id=${HF_USER}/koch_test \
   policy=act_koch_real \
   env=koch_real \
@@ -918,7 +915,6 @@ env:
 It should match your dataset (e.g. `fps: 30`) and your robot (e.g. `state_dim: 6` and `action_dim: 6`). We are still working on simplifying this in future versions of `lerobot`.
 4. We provided `device=cuda` since we are training on a Nvidia GPU, but you could use `device=mps` to train on Apple silicon.
 5. We provided `wandb.enable=true` to use [Weights and Biases](https://docs.wandb.ai/quickstart) for visualizing training plots. This is optional but if you use it, make sure you are logged in by running `wandb login`.
-6. We added `DATA_DIR=data` to access your dataset stored in your local `data` directory. If you dont provide `DATA_DIR`, your dataset will be downloaded from Hugging Face hub to your cache folder `$HOME/.cache/hugginface`. In future versions of `lerobot`, both directories will be in sync.
 
 For more information on the `train` script see the previous tutorial: [`examples/4_train_policy_with_script.md`](../examples/4_train_policy_with_script.md)
 
@@ -991,7 +987,6 @@ To this end, you can use the `record` function from [`lerobot/scripts/control_ro
 python lerobot/scripts/control_robot.py record \
   --robot-path lerobot/configs/robot/koch.yaml \
   --fps 30 \
-  --root data \
   --repo-id ${HF_USER}/eval_koch_test \
   --tags tutorial eval \
   --warmup-time-s 5 \
@@ -1010,7 +1005,6 @@ As you can see, it's almost the same command as previously used to record your t
 You can then visualize your evaluation dataset by running the same command as before but with the new inference dataset as argument:
 ```bash
 python lerobot/scripts/visualize_dataset.py \
-  --root data \
   --repo-id ${HF_USER}/eval_koch_test
 ```