glibc git commit hooks update.

[Florian Weimer]

* DJ Delorie:

> For the benefit of those of us who aren't git-savvy, could you please
> summarize what a long-term in-branch development process should look
> like?  I.e. one that's optimal for our new configuration on sourceware?
>
> I recall going through that with the tcache work, constantly merging
> master into the branch, flooding irc, messing up my local repo, and I
> recall it was... suboptimal.

You can do whatever you want on the private branches.  IRC, email,
Bugzilla updates are all disabled as of today.

In theory, too many private branches could cause repository bloat, but
given the amount of history we carry around anyway, I don't expect
this to be a substantial issue.