GRN2-45, GRN2-197: Upgrade Rails to 5.2.3 and removed sass-rails gem (#636)

* Removed deprecate sass-rails and replace with sassc-rails

* Upgraded to Rails 5.2.3

* Fixed travis

* Added back Spring code

* Fixed travis again

config/environments/production.rb

@@ -16,6 +16,10 @@ Rails.application.configure do
   config.consider_all_requests_local       = false
   config.action_controller.perform_caching = true
 
+  # Ensures that a master key has been made available in either ENV["RAILS_MASTER_KEY"]
+  # or in config/master.key. This key is used to decrypt credentials (and other encrypted files).
+  # config.require_master_key = true
+
   # Disable serving static files from the `/public` folder by default since
   # Apache or NGINX already handles this.
   config.public_file_server.enabled = ENV['RAILS_SERVE_STATIC_FILES'].blank?
@@ -36,6 +40,9 @@ Rails.application.configure do
   # config.action_dispatch.x_sendfile_header = 'X-Sendfile' # for Apache
   # config.action_dispatch.x_sendfile_header = 'X-Accel-Redirect' # for NGINX
 
+  # Store uploaded files on the local file system (see config/storage.yml for options)
+  config.active_storage.service = :local
+
   # Mount Action Cable outside main process or domain
   # config.action_cable.mount_path = nil
   # config.action_cable.url = 'wss://example.com/cable'