Refer to module by suitable file name (mod_*.c).
Test for mod_authz_core.c (instead of mod_authz_host.c) to properly
detect Apache 2.4 and avoid false positive for Apache 2.2.

- solves mixed content warnings on web security analyzers
- saves time since http://php.net/images/php.gif will redirect to https://secure.php.net/images/php.gif anyway.

Access attempts to security.png are normally denied, so the name of the file will be more self-descriptive

Improves syntax page due to feedback at #1233

Signed-off-by: Robin H. Johnson <robbat2@gentoo.org>

Signed-off-by: Robin H. Johnson <robbat2@gentoo.org>

We now use phpversion() instead of php_logo_guid()