Update README.md

README.md

@@ -4,15 +4,15 @@ PowerAPI is a middleware toolkit for building software-defined power meters. Sof
 # About
 PowerAPI is an open-source project developed by the [Spirals research group](https://team.inria.fr/spirals) (University of Lille 1 and Inria).
 
-# Mailing list
+## Mailing list
 You can follow the latest news and asks questions by subscribing to our [mailing list](https://sympa.inria.fr/sympa/info/powerapi).
 
-# Contributing
+## Contributing
 If you would like to contribute code you can do so through GitHub by forking the repository and sending a pull request.
 
 When submitting code, please make every effort to follow existing conventions and style in order to keep the code as readable as possible.
 
-# Acknowledgments
+## Acknowledgments
 We all stand on the shoulders of giants and get by with a little help from our friends. PowerAPI is written in [Scala](http://www.scala-lang.org) (version 2.11.4 under [3-clause BSD license](http://www.scala-lang.org/license.html)) and built on top of:
 * [Akka](http://akka.io) (version 2.3.6 under [Apache 2 license](http://www.apache.org/licenses/LICENSE-2.0)), for asynchronous processing
 * [Typesage Config](https://github.com/typesafehub/config) (version 1.2.1 under [Apache 2 license](http://www.apache.org/licenses/LICENSE-2.0)), for reading configuration files.