(1) Use PyErr_NewException("module.class", NULL, NULL) to create the
exception object.
(2) Remove all calls to Py_FatalError(); instead, return or
ignore the errors -- the import code now checks PyErr_Occurred()
after calling a module's init function, so it's no longer a
fatal error for the initialization to fail.
Also did some small cleanups, e.g. removed unnecessary test for
"already initialized" from initfpectl(), and unified
initposix()/initnt().
I haven't checked this very thoroughly, so while the changes are
pretty trivial -- beware of untested code!
Removed handling of \e, \cX escapes, following a string-SIG discussion.
Fixed minor typos in re.py
re.error is now set equal to reop.error.
Move definition of constants like NORMAL and CHARCLASS into reop, which
exports them; re.py was changed to import them from reop.
Added C equivalents of _expand and expand_escape to reop, and changed
re.py to use them.