New organisation is set using the url region

app/controllers/orgas_controller.rb

@@ -17,7 +17,7 @@ class OrgasController < ApplicationController
 
   # GET /orgas/new
   def new
-    @orga = Orga.new
+    @orga = Orga.new region_id: params[:region]
   end
 
   # POST /orgas

app/views/layouts/application.html.haml

@@ -34,10 +34,10 @@
 
     %footer.bottom
       %nav
-        = link_to new_event_path do
+        = link_to new_event_path region: params[:region] do
           %em.fa.fa-pencil
           = t '.propose'
-        = link_to new_orga_path do
+        = link_to new_orga_path region: params[:region] do
           %em.fa.fa-users
           = t '.propose_orga'
         %br/