[Developers] synchronise all processors before aborting on parameter errors

[Bela Szilagyi]

I definitely don't seem to have to wait 5 seconds before the job aborts in 
case of incorrect parameters.  



> It does sleep already before calling abort(). I committed that patch to
> src/comm/CactusDefaultComm.c back in 2003 already, although it has the
> delay hard-coded to 5 seconds. Is that not enough ?
>
> > Makes sense (although needs to be a separate commit).
>
> Okay, I will then just commit the CCTK_Barrier() in
> CCTKi_FinaliseParamWarn().