note mod_authz_user dependency for example usage
remove config sample, the README should cover it all
make it work on apache-2.2 again
rename custom header, per RFC 6648
Merge remote-tracking branch 'upstream/master'

Conflicts:
	src/defines.h
	src/mod_authnz_persona.c
forgot to fix the assertion header
Correctly ensure cookie defaults are set
Make sure test httpd config works against 2.2 and 2.4+