Rewrite packages README after monorepo split

Author: yann-eugone

README.md

@@ -1,23 +1,47 @@
-# Yokai Batch
+# symfony/serializer bridge for Batch processing library
 
 [![Latest Stable Version](https://img.shields.io/packagist/v/yokai/batch-symfony-serializer?style=flat-square)](https://packagist.org/packages/yokai/batch-symfony-serializer)
 [![Downloads Monthly](https://img.shields.io/packagist/dm/yokai/batch-symfony-serializer?style=flat-square)](https://packagist.org/packages/yokai/batch-symfony-serializer)
 
-Bridge of [`symfony/serializer`](https://github.com/symfony/serializer) for [Batch](https://github.com/yokai-php/batch-src).
+Bridge of [`symfony/serializer`](https://github.com/symfony/serializer) for [Batch](https://github.com/yokai-php/batch).
+
+
+## :warning: BETA
+
+This library is following [semver](https://semver.org/).
+However before we reach the first stable version (`v1.0.0`), we may decide to introduce **API changes in minor versions**.
+This is why you should stick to a `v0.[minor].*` requirement !
+
+
+# Installation
+
+```
+composer require yokai/batch-symfony-serializer
+```
 
 
 ## Documentation
 
-Please refer to [main repository](https://github.com/yokai-php/batch-src) documentation.
+This package provides:
+
+- an [item processor](docs/normalize-item-processor.md) that uses normalization
+- an [item processor](docs/denormalize-item-processor.md) that uses denormalization
+- a [job execution serializer](docs/job-execution-serializer.md) that uses serialization
 
 
 ## Contribution
 
+This package is a readonly split of a [larger repository](https://github.com/yokai-php/batch-src),
+containing all tests and sources for all librairies of the batch universe.
+
 Please feel free to open an [issue](https://github.com/yokai-php/batch-src/issues)
 or a [pull request](https://github.com/yokai-php/batch-src/pulls)
 in the [main repository](https://github.com/yokai-php/batch-src).
 
+The library was originally created by [Yann Eugoné](https://github.com/yann-eugone).
+See the list of [contributors](https://github.com/yokai-php/batch-src/contributors).
+
 
-## MIT License
+## License
 
-License can be found [here](LICENSE).
+This library is under MIT [LICENSE](LICENSE).

docs/denormalize-item-processor.md

@@ -0,0 +1 @@
+todo

docs/job-execution-serializer.md

@@ -0,0 +1 @@
+todo

docs/normalize-item-processor.md

@@ -0,0 +1 @@
+todo