Add C API function Py_GetBuildNumber(), add it to the interactive prompt
banner (i.e. Py_GetBuildInfo()), and add it as the sys.build_number
attribute. The build number is a string instead of an int because it may
contain a trailing 'M' if there are local modifications.
Strip off leading dots and slash so the generated files are the same regardless
of whether you configure in the checkout directory or build.
If anyone configures in a different directory, we might want a cleaner
approach using os.path.*(). Hopefully this is good enough.
If a line had multiple semi-colons and ended with a semi-colon, we would
loop too many times and access a NULL node. Exit the loop early if
there are no more children.
In C++, it's an error to pass a string literal to a char* function
without a const_cast(). Rather than require every C++ extension
module to put a cast around string literals, fix the API to state the
const-ness.
I focused on parts of the API where people usually pass literals:
PyArg_ParseTuple() and friends, Py_BuildValue(), PyMethodDef, the type
slots, etc. Predictably, there were a large set of functions that
needed to be fixed as a result of these changes. The most pervasive
change was to make the keyword args list passed to
PyArg_ParseTupleAndKewords() to be a const char *kwlist[].
One cast was required as a result of the changes: A type object
mallocs the memory for its tp_doc slot and later frees it.
PyTypeObject says that tp_doc is const char *; but if the type was
created by type_new(), we know it is safe to cast to char *.
