doc(link): add doc for link_custom

docker/settings_local.template.py

@@ -99,3 +99,6 @@ OPTIONNAL_APPS_RE2O = ()
 
 # Some Django apps you want to add in you local project
 OPTIONNAL_APPS = OPTIONNAL_APPS_RE2O + ()
+
+# Some optinnal link for the navbar in a tuple (link,class,text)
+OPTIONNAL_LINK_RE2O = ()

re2o/settings_local.example.py

@@ -118,7 +118,9 @@ OPTIONNAL_APPS_RE2O = ()
 # Some Django apps you want to add in you local project
 OPTIONNAL_APPS = OPTIONNAL_APPS_RE2O + ()
 
-OPTIONNAL_LINK_RE2O= ()
+# Some optinnal link for the navbar in a tuple (link,class,text)
+OPTIONNAL_LINK_RE2O = ()
+
 # Add statiffiles dir that were installed using system packaging
 # Example to reproduce re2o2.9 behavior
 # SYSTEM_STATICFILES_DIRS = ("/usr/share/fonts-font-awesome/", "/usr/share/javascript/")