C++0x support macros

[David Nolden]

Btw. I would prefer you to do most of the work in master (of course as
long as all tests pass and you're only "adding" functionality).

I think, for a core contributor, a branch makes only sense for really
large changes, or changes with temporary regressions, or experiments
where it's unclear whether they will work or will be finished.

I think that the C++ 0x support will rather be a set of small, more or
less independent, and incremental changes, each of which should go
into master as soon as it's ready.

Greetings, David