Merge from trunk:

  Unix MPMs: Catch SIGFPE so that exception hooks and CoreDumpDirectory
  can work after that terminating signal.

Submitted by: Eric Covener <covener gmail.com>
Reviewed by: trawick, rpluem, jorton


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.2.x@501130 13f79535-47bb-0310-9956-ffa450edef68