Message 413116 - Python tracker

I think making more objects immortal by default will reduce the gap, although I am not sure it can be 2%. (I guess 3% and I think it is acceptable gap.)

* Code attributes (contents of co_consts, co_names, etc...) in deep frozen modules.
  * only if subinterpreter shares them.
* Statically allocated strings (previously _Py_IDENTIFIER)

To reduce gap more, we need to reduce Python stack operation in ceval in some way.