Add link to communication.md

ideas.md

@@ -13,9 +13,9 @@
 This page hosts the ideas GitLab proposes for Google Summer of Code 2016.
-You can discuss the ideas posted here or create a new topic with your idea
-in our [forum](https://forum.gitlab.com/c/gsoc/gsoc-2016) (tip: you can login
-using your GitLab.com credentials).
+You can [discuss](communication.md) the ideas posted here or create a new topic
+with your idea in our [forum](https://forum.gitlab.com/c/gsoc/gsoc-2016) (tip:
+you can login using your GitLab.com credentials).
 ---