Added a new API for NetWare to allow Apache the chance to unimport

  module symbols before it shuts down.

    void ap_os_dso_unsym(void *handle, const char *symname)

  This is necessary so that Apache on NetWare can shutdown cleanly
  in an error condition such as a failure while reading the .CONF file.

Submitted by:	Brad Nicholes <BNICHOLES@novell.com>
Reviewed by:	William Rowe


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@88364 13f79535-47bb-0310-9956-ffa450edef68