Send salmons and websub in background tasks.

lib/pleroma/web/salmon/salmon.ex

@@ -150,8 +150,10 @@ def publish(%{info: %{"keys" => keys}} = user, activity, poster) do
 
       remote_users(activity)
       |> Enum.each(fn(remote_user) ->
-        Logger.debug(fn -> "sending salmon to #{remote_user.ap_id}" end)
-        send_to_user(remote_user, feed, poster)
+        Task.start(fn ->
+          Logger.debug(fn -> "sending salmon to #{remote_user.ap_id}" end)
+          send_to_user(remote_user, feed, poster)
+        end)
       end)
     end
   end

lib/pleroma/web/websub/websub.ex

@@ -51,10 +51,12 @@ def publish(topic, user, activity) do
       signature = sign(sub.secret || "", response)
       Logger.debug(fn -> "Pushing to #{sub.callback}" end)
 
-      @httpoison.post(sub.callback, response, [
-            {"Content-Type", "application/atom+xml"},
-            {"X-Hub-Signature", "sha1=#{signature}"}
-          ])
+      Task.start(fn ->
+        @httpoison.post(sub.callback, response, [
+              {"Content-Type", "application/atom+xml"},
+              {"X-Hub-Signature", "sha1=#{signature}"}
+            ])
+      end)
     end)
   end