new talloc stuff

[tridge at samba.org]

Metze,

 > is the talloc stuff thread safe, I notice all the DLIST_* ops,
 > (maybe I need to look at the code more detailed:-)

It's as thread safe as the old talloc code :)

What I mean by that, is that as long as each thread is operating on
different memory contexts then it is safe. If two threads operate on
the same context at the same time then it would not be safe.

Luckily the design of the process model in Samba4 means that the
threads do operate on separate memory contexts. (there are some
exceptions to this, but my changes didn't make them any worse)

Cheers, Tridge