improve documentation

Fix multiple typos in the internal documentation

Improve visual aspect and redaction

README.md

 # Duniter v2s
 
-<img alt="logov2" src="https://duniter.fr/img/duniterv2.svg" width="128" height="128"/>
+🆙 A rewriting of [Duniter v1](https://duniter.org) in the [Substrate](https://www.substrate.io/) framework.
+
+⚠️ Duniter-v2s is under active development.
 
-A rewriting of [Duniter](https://duniter.org) based on [Substrate](https://www.substrate.io/) framework.
+🚧 A test network called "ĞDev" is deployed, allowing to test wallets and indexers.
 
-duniter-v2s is under active development, only a test network called "ĞDev" is deployed.
+<img alt="logov2" src="https://duniter.fr/img/duniterv2.svg" width="128" height="128"/>
 
 ## Documentation TOC