Added spec to verify that memory executor accepts options

Author: Ary Borenszweig

spec/rgviz/memory_executor_spec.rb

@@ -552,4 +552,9 @@ def self.it_processes_single_select_column(query, id, type, value, label, test_o
       i += 1
     end
   end
+
+  it "accepts options" do
+    exec = MemoryExecutor.new [], Types
+    exec.execute "select *", {}
+  end
 end