Merge pull request #56 from basho/rdb-spiral-delete

Change the order of delete cascade for `spiral'
diff --git a/src/folsom_ets.erl b/src/folsom_ets.erl
index edd2f36..8a223c5 100644
--- a/src/folsom_ets.erl
+++ b/src/folsom_ets.erl
@@ -300,9 +300,9 @@
 delete_metric(Name, spiral) ->
     #spiral{tid=Tid, server=Pid} = folsom_metrics_spiral:get_value(Name),
     folsom_sample_slide_server:stop(Pid),
-    true = ets:delete(Tid),
     ets:delete(?SPIRAL_TABLE, Name),
     ets:delete(?FOLSOM_TABLE, Name),
+    ets:delete(Tid),
     ok.
 
 delete_histogram(Name, #histogram{type = uniform, sample = #uniform{reservoir = Reservoir}}) ->