Better docs

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

Nicer docs

No 3rd stage

Add mix.deps get before docs

Add :ex_doc on test env so that it runs into CI

support/guides/introduction.md

@@ -0,0 +1,64 @@
+# Mobilizon
+
+<p align="center">
+    <a href="https://joinmobilizon.org">
+        <img src="http://lutim.cpy.re/m9Y8rXRU.png" alt="Mobilizon">
+    </a>
+</p>
+
+MobiliZon is your federated organization and mobilization platform. Gather people with a convivial, ethical, and emancipating tool.
+
+<p align="center">
+  <strong>Developed with ♥ by <a href="https://framasoft.org">Framasoft</a></strong>
+</p>
+
+<p align="center">
+  <a href="https://framasoft.org">
+    <img width="150px" src="http://lutim.cpy.re/Prd3ci7G.png" alt="Framasoft logo"/>
+  </a>
+</p>
+
+## Introduction
+
+Mobilizon is a tool designed to create platforms for managing communities and events. Its purpose is to help as many people as possible to free themselves from Facebook groups and events, from Meetup, etc.
+
+The MobiliZon software is under a Free licence, so anyone can host a MobiliZon server, called an instance. These instances may federate with each other, so any person with an account on *ExampleMeet* will be able to register to an event created on *SpecimenEvent*.
+
+## ✨ Features
+
+### 👤 Identities
+
+Do you want to separate your family gatherings from your associative activities or militant mobilizations?
+You will have the power to create multiple identities from the same account, like so many social masks.
+
+---
+
+### 📅 Events and groups
+
+Create your events and make sure they will appeal to everybody. 
+Privacy settings and participants roles are supported.
+There's no lock-in, you can interact with the event without registration.
+
+---
+
+## Contributing
+
+We appreciate any contribution to MobiliZon. Check our [CONTRIBUTING](contributing.html) file for more information.
+
+## Links
+
+### Learn more
+  * 🌐 Official website: [https://joinmobilizon.org](https://joinmobilizon.org)
+  * 💻 Source: [https://framagit.org/framasoft/mobilizon](https://framagit.org/framasoft/mobilizon)
+  * 📝 Wiki: [https://framagit.org/framasoft/mobilizon/wikis/home](https://framagit.org/framasoft/mobilizon/wikis/home)
+  
+### Discuss
+  * 💬 Matrix: `#Mobilizon:matrix.org` [Riot](https://riot.im/app/#/room/#Mobilizon:matrix.org)
+  * #️⃣   IRC `#mobilizon` on Freenode
+  * 🗣️ Forum: [https://framacolibri.org/c/mobilizon](https://framacolibri.org/c/mobilizon)
+
+### Follow
+  * 🐘 Mastodon: [https://framapiaf.org/@mobilizon](https://framapiaf.org/@mobilizon)
+  * 🐦 Twitter [https://twitter.com/@joinmobilizon](https://twitter.com/@joinmobilizon)
+  
+Note: Most federation code comes from [Pleroma](https://pleroma.social), which is `Copyright © 2017-2018 Pleroma Authors - AGPL-3.0`