[v3] C headers, part 1

[Loren James Rittle]

> I think you should be fine, because libsupc++ is not really touched. 

Humm, I think my patch currently touches src/Makefile.am in the same
area that you are working on.

>> Yow!  I am going to have to completely rework the configuration part

> How do you want to do this? Do you want to check in first?

Yes, since then you get to do the merge. ;-) but I am happy to work
with you on that point.

Dave still has some valid concerns that I am attempting to address but
I think we could go on the mainline, if you want and with the
expectation that some tweaks will continue to go in (although they
will be confined to stl_threads.h.

Regards,
Loren