Recursive Include directives no longer crash. The server stops

including configuration files after a certain nesting level (128
as distributed). This is configurable at compile time using the
-DAP_MAX_INCLUDE_DEPTH switch.

PR: 28370


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@103466 13f79535-47bb-0310-9956-ffa450edef68