Add systemd support

[David Disseldorp]

Hi Sumit,

Finally getting back to this, sorry for the wait.

On Thu, 2 Feb 2012 15:53:52 +0100
Sumit Bose <sbose at redhat.com> wrote:

> > It may also be worth considering a LimitNOFILE setting, ctdbd requires
> > one fd per client, exceeding the default limit under heavy load results
> > in a busy EMFILE loop around accept() (at least it did in ctdb-1.0.112).  
> 
> Please have a look at the new patch 0001, is this what you thought of?

The changes look good to me, thanks for submitting. FWIW it looks like
ctdb.sysconfig already has a commented out ulimit -n setting so patch
0001 may not be necessary.

Cheers, David