Fix route options update behavior

Author: hoffmaen

app/actions/route_update.rb

@@ -2,7 +2,15 @@ module VCAP::CloudController
   class RouteUpdate
     def update(route:, message:)
       Route.db.transaction do
-        route.options = message.options if message.requested?(:options)
+        if message.requested?(:options)
+          route.options = if message.options.nil?
+                            nil
+                          elsif route.options.nil?
+                            message.options
+                          else
+                            route.options.merge(message.options)
+                          end
+        end
         route.save
         MetadataUpdate.update(route, message)
       end