remove call to engine.close() - engine does not have such a method (fixes issue #24)

Author: adamhadani

rdflib_sqlalchemy/store.py

@@ -619,8 +619,6 @@ def close(self, commit_pending_transaction=False):
         Close the current store engine connection if one is open.
 
         """
-        if self.engine:
-            self.engine.close()
         self.engine = None
 
     def destroy(self, configuration):