FEATURE: per host regular jobs

These are jobs that will run on every host that is running discourse.

If you have multiple hosts running the same site you get independent
schedules

lib/scheduler/schedule_info.rb

@@ -86,6 +86,7 @@ module Scheduler
     end
 
     def write!
+
       clear!
       redis.set key, {
         next_run: @next_run,
@@ -95,7 +96,7 @@ module Scheduler
         current_owner: @current_owner
       }.to_json
 
-      redis.zadd Manager.queue_key, @next_run , @klass
+      redis.zadd queue_key, @next_run , @klass
     end
 
     def del!
@@ -104,7 +105,19 @@ module Scheduler
     end
 
     def key
-      Manager.schedule_key(@klass)
+      if @klass.is_per_host
+        Manager.schedule_key(@klass, @manager.hostname)
+      else
+        Manager.schedule_key(@klass)
+      end
+    end
+
+    def queue_key
+      if @klass.is_per_host
+        Manager.queue_key(@manager.hostname)
+      else
+        Manager.queue_key
+      end
     end
 
     def redis
@@ -114,7 +127,7 @@ module Scheduler
     private
     def clear!
       redis.del key
-      redis.zrem Manager.queue_key, @klass
+      redis.zrem queue_key, @klass
     end
 
   end