Added WSGI support. Created core.handlers package. Moved ALL mod_python-specific code to django.core.handlers.modpython. Note that django.core.handler is still a valid mod_python handler but IS DEPRECATED. Use django.core.handlers.modpython, instead.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@169 bcc190cf-cafb-0310-a4f2-bffc1f526a37