this fixes the build error on windows. I can make it windows only but its probably not needed for the other platforms as well.
Windows seemed to use the config.h from pcre which is no longer and thus the builds fails.
If UNICODE is defined via config.h for other platforms we might guard it with #ifdef HAVE_CONFIG_H
[WIN32] fixed win build by guarding config.h with HAVE_CONFIG_H
I wrapped the config.h in HAVE_CONFIG_H and merge it in a few if nobody objects.