apr project (abspath includes in RSC targets), and add srclib
targets to the system INCLUDE path so that these are excluded
from the dependencies; seperate builds will work without the
srclib/ files.
git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.2.x@1100445 13f79535-47bb-0310-9956-ffa450edef68