Add basic self hosted onboarding (#1177)

* Add basic self hosted onboarding

* Lint fix

* Normalize translations

app/controllers/concerns/invitable.rb

@@ -7,6 +7,10 @@ module Invitable
 
   private
     def invite_code_required?
-      ENV["REQUIRE_INVITE_CODE"] == "true"
+      self_hosted? ? Setting.require_invite_for_signup : ENV["REQUIRE_INVITE_CODE"] == "true"
+    end
+
+    def self_hosted?
+      Rails.application.config.app_mode.self_hosted?
     end
 end