This adds most of the metadata infrastructure: I think that all commands

This adds most of the metadata infrastructure: I think that all commands
(mkdir, link, symlink, rm, rmdir, mknod, mv etc) now work.  Probably the
server code is not multithread safe (particularly for renames, the others
might be OK).   I expect other fragilities and perhaps some errors with
setting {a,m,c}times, owners etc.

- add the beginning of an obd command that prints the information
  for UML gdb (class/class_obd.c)
- try to ignore errors on creating symbolic links in Makefiles
- the patch is 2.4.17 again for ext2obd, ghees, let's fix that.
- to avoid confusion, null out the buffer of result nio's in prepw
- add other reintegration functions.