Add spec helper that waits for the next second to begin (instead of sleeping for a whole second)

spec/directories_spec.rb

@@ -122,7 +122,7 @@ describe "Directories" do
         end
 
         it "updates the timestamp of the directory" do
-          sleep 1
+          wait_a_second
           put "/jimmy/tasks/home/trash", "take out the trash"
 
           @directory.reload

spec/spec_helper.rb

@@ -43,4 +43,9 @@ def purge_all_buckets
   end
 end
 
+def wait_a_second
+  now = Time.now.to_i
+  while Time.now.to_i == now; end
+end
+
 alias context describe