improve documentation

Fix multiple typos in the internal documentation

Improve visual aspect and redaction

docs/user/rpc.md

@@ -19,8 +19,9 @@ Your `PEER_ID` shoud be generated with this command: `docker run --rm -it --ent
 
 ### Reverse-proxy part (with Nginx)
 
-In `/etc/nginx/sites-enabled/gdev.YOUR_DOMAIN` put (you can probably do simpler) :
-```
+In `/etc/nginx/sites-enabled/gdev.YOUR_DOMAIN` put (you can probably do simpler):
+
+```nginx
 server {
   server_name gdev.YOUR_DOMAIN.fr;