Adds README

README.md

+# Hydra tutorial
+
+This repository contains a very simple network training using pytorch lightning flash.
+The configuration management is done using Hydra (https://hydra.cc/), as the goal
+of this code is to showcase how Hydra can be used.
+
+## Installing
+
+You can install this code with poetry (install poetry at : https://python-poetry.org/docs/#installation) using : 
+
+```
+poetry install
+```
+
+## Running
+
+Once the project has been installed, you can run it with the following command:
+
+```
+poetry run flashtrain
+```
+
+You can, for example, change the learning rate using : 
+
+```
+poetry run flashtrain model.learning_rate=1e-2
+```
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