Remove /usr/include/event.h because it conflicts with libevent
Update to 4.24 although it doesn't bring anything as you can see:
- bump version to 4.24, as the release tarball inexplicably didn't have the right version in ev.h, even though the cvs-tagged version did have the right one.
- move some declarations at the beginning to help certain retarded microsoft compilers, even though their documentation claims otherwise.
Signed-off-by: Pierre-Yves <firstname.lastname@example.org>