Upgraded to Rails 5.1.1

config/environments/production.rb

@@ -90,7 +90,7 @@ Wrestling::Application.configure do
 
   #THESE ADDED BY ME TO GET RAILS 4 WORKING IN HEROKU
   config.cache_classes = true
-  config.serve_static_files = true
+  config.public_file_server.enabled = true
   config.assets.compile = true
   config.assets.digest = true
 
@@ -111,6 +111,4 @@ Wrestling::Application.configure do
     #Devise needs origin of email
     Rails.application.routes.default_url_options[:host] = 'https://wrestlingdev.com'
 
-    #For lineman creating assets
-    config.serve_static_files = true
 end

config/environments/test.rb

@@ -13,8 +13,8 @@ Wrestling::Application.configure do
   config.eager_load = false
 
   # Configure static asset server for tests with Cache-Control for performance.
-  config.serve_static_files  = true
-  config.static_cache_control = "public, max-age=3600"
+  config.public_file_server.enabled = true
+  config.public_file_server.headers = { 'Cache-Control' => 'public, max-age=3600' }
 
   # Show full error reports and disable caching.
   config.consider_all_requests_local       = true