add missing ifdefs in header files


git-svn-id: https://gnunet.org/svn/gnunet@32584 140774ce-b5e7-0310-ab8b-a85725594a96
- Copy PATHS section as the shared service configuration may refer to options from here.


git-svn-id: https://gnunet.org/svn/gnunet@32585 140774ce-b5e7-0310-ab8b-a85725594a96
- Warn upon deleting unsent message.
- Send the message immediately if its size equals to the buffer size.


git-svn-id: https://gnunet.org/svn/gnunet@32586 140774ce-b5e7-0310-ab8b-a85725594a96