Upgrade to rails 6 💎 (#11)

- upgraded to rails 6
- fixes various issues

config/application.rb

@@ -1,12 +1,17 @@
 require_relative 'boot'
 
 require "rails"
+# Pick the frameworks you want:
 require "active_model/railtie"
 require "active_job/railtie"
 require "active_record/railtie"
+require "active_storage/engine"
 require "action_controller/railtie"
 require "action_mailer/railtie"
+require "action_mailbox/engine"
+require "action_text/engine"
 require "action_view/railtie"
+# require "action_cable/engine"
 require "sprockets/railtie"
 require "rails/test_unit/railtie"
 
@@ -16,20 +21,16 @@ Bundler.require(*Rails.groups)
 
 module Chatwoot
   class Application < Rails::Application
-    # Settings in config/environments/* take precedence over those specified here.
-    # Application configuration should go into files in config/initializers
-    # -- all .rb files in that directory are automatically loaded.
+    # Initialize configuration defaults for originally generated Rails version.
+    config.load_defaults 5.0
     config.paths.add File.join('app', 'bot'), glob: File.join('**', '*.rb')
     config.autoload_paths += Dir[Rails.root.join('app', 'bot', '*')]
     config.autoload_paths << Rails.root.join('lib')
     config.eager_load_paths << Rails.root.join('lib')
-    config.assets.enabled = false
-    config.middleware.insert_before 0, Rack::Cors do
-      allow do
-        origins '*'
-        resource '*', :headers => :any, :methods => [:get, :post, :options, :delete, :put, :patch], :expose => ['access-token', 'client', 'uid', 'expiry']
-      end
-    end
 
+    # Settings in config/environments/* take precedence over those specified here.
+    # Application configuration can go into files in config/initializers
+    # -- all .rb files in that directory are automatically loaded after loading
+    # the framework and any gems in your application.
   end
 end