Update README.md

More explicit name of the link to the rules, cf. I could not find myself where the link to the rules was.

Author: mcandito

README.md

@@ -7,4 +7,4 @@ This project contains:
  * `UD_French-Sequioa`: automatic conversion of the [`UD_French-Sequioa`](https://github.com/UniversalDependencies/UD_French-Sequoia) corpus (see [Details](UD_French-Sequoia))
  * `UD_French`: automatic conversion of the [`UD_French`](https://github.com/UniversalDependencies/UD_French) corpus (see [Details](UD_French))
 
-The graph rewriting system used in [**Grew**](http://grew.loria.fr) for the conversion is available on [`gitlab.inria.fr`](https://gitlab.inria.fr/grew/UDtoAUD).
+The graph rewriting system used in [**Grew**](http://grew.loria.fr) for the conversion is available at [`gitlab.inria.fr/grew/UDtoAUD`](https://gitlab.inria.fr/grew/UDtoAUD).