Protected stream closure against possibilty of being a bytes

For some reason, it gets bytes where it did expect a stream ... .
Probably I should have figured out where this was input, instead
of fixing it the brutal way

Author: Byron

gitdb/db/loose.py

@@ -159,7 +159,8 @@ def info(self, sha):
             typ, size = loose_object_header_info(m)
             return OInfo(sha, typ, size)
         finally:
-            m.close()
+            if hasattr(m, 'close'):
+                m.close()
         # END assure release of system resources
 
     def stream(self, sha):

gitdb/stream.py

@@ -145,7 +145,8 @@ def close(self):
         :note: can be called safely 
         """
         if self._close:
-            self._m.close()
+            if hasattr(self._m, 'close'):
+                self._m.close()
             self._close = False
         # END handle resource freeing