Note required Maven version

CONTRIBUTING.md

@@ -14,6 +14,9 @@ git submodules init
 git submodules update
 ```
 
+### Dependencies
+* Requires Maven 3.2 or higher, tested on Apache Maven 3.2.1 and 3.3.3.
+
 ### Setting up your IDE
 *These steps were only tested for Eclipse and IntelliJ.*
 To succesfully run and test Devhub, a couple of steps should be followed to setup various dependencies and configurations.
@@ -78,4 +81,4 @@ java -jar git-server/target/git-server-distribution/git-server/git-server.jar
 The `GitServerClientImpl` connects to the address read from the `config.properties` file (default: `http://localhost:8081`).
 
 ### Further reading
-Before contributing to Devhub it's hugely recommended to read upon JAX-RS (we use the [Resteasy](http://docs.jboss.org/resteasy/docs/3.0.9.Final/userguide/html/index.html) implementation), JPA (we use [Hibernate](http://docs.jboss.org/hibernate/orm/4.3/manual/en-US/html/)), [Freemarker](http://freemarker.org/docs/index.html) and [Google Guice](https://github.com/google/guice/wiki/Motivation) dependency injection.
+Before contributing to Devhub it's hugely recommended to read upon JAX-RS (we use the [Resteasy](http://docs.jboss.org/resteasy/docs/3.0.9.Final/userguide/html/index.html) implementation), JPA (we use [Hibernate](http://docs.jboss.org/hibernate/orm/4.3/manual/en-US/html/)), [Freemarker](http://freemarker.org/docs/index.html) and [Google Guice](https://github.com/google/guice/wiki/Motivation) dependency injection.