First pass at mod_include as a filter. This is at an incredibly alpha

stage, but it should compile for everybody now.  I have experienced a few
seg faults that I haven't been able to track down yet, but it should
compile on all platforms, which is better than before this patch.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@86211 13f79535-47bb-0310-9956-ffa450edef68