Made some improvements to ACL system including: warning on setting Deny for Everyone on the entire site, added ACL_ALWAYS_ALLOW_ADMIN_EDIT_ACL, and changed behavior as noted in the docs so that Deny for Everyone is no longer able to be overridden

# Used for testing mod_rewrite.
<IfModule mod_rewrite.c>
RewriteEngine on

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule (.*) install.php?do=modrewrite_test&str=$1
</IfModule>