The new function is now responsible to parse -E and -I command line arguments.
* Add _PyPreConfig structure * Move 'ignored' and 'use_environment' fields from _PyCoreConfig to _PyPreConfig * Add a new "_PyPreConfig preconfig;" field to _PyCoreConfig
* Add _PyArgv_Decode() function * Move _Py_ClearFileSystemEncoding() and _Py_SetFileSystemEncoding() to preconfig.c.