Updated all the README files

Author: javiereguiluz

README.md

@@ -1,17 +1,15 @@
 Config Component
 ================
 
-Config provides the infrastructure for loading configurations from different
-data sources and optionally monitoring these data sources for changes. There
-are additional tools for validating, normalizing and handling of defaults that
-can optionally be used to convert from different formats to arrays.
+The Config component provides several classes to help you find, load, combine,
+autofill and validate configuration values of any kind, whatever their source
+may be (YAML, XML, INI files, or for instance a database).
 
 Resources
 ---------
 
-You can run the unit tests with the following command:
-
-    $ cd path/to/Symfony/Component/Config/
-    $ composer install
-    $ phpunit
-
+  * [Documentation](https://symfony.com/doc/current/components/config/index.html)
+  * [Contributing](https://symfony.com/doc/current/contributing/index.html)
+  * [Report issues](https://github.com/symfony/symfony/issues) and
+    [send Pull Requests](https://github.com/symfony/symfony/pulls)
+    in the [main Symfony repository](https://github.com/symfony/symfony)