Applied patch zombie-frames-2.diff from sf patch 876206 with updates for
Python 2.5 and also modified to retain the free_list to avoid the 67%
slow-down in pybench recursion test. 5% speed up in function call pybench.
This change implements a new bytecode compiler, based on a
transformation of the parse tree to an abstract syntax defined in
Parser/Python.asdl.
The compiler implementation is not complete, but it is in stable
enough shape to run the entire test suite excepting two disabled
tests.