[patch] Update libstdc++ FAQ and ensure stable anchors in HTML docs

[Gerald Pfeifer]

On Mon, 9 Jun 2014, Jonathan Wakely wrote:
> This fairly tedious patch refreshes the FAQ, including adding some
> notes saying "This answer is old and probably no longer relevant" to
> several answers referring to problems in the GCC 3.x era.

I'm wondering, should those old items be removed?  GCC 3.x is
really a looong while ago (and I did check some of those items).

A FAQ that containts many NAFAQs (not actually frequently asked 
questions) may actually be less useful and paint a more negative
picture.

Gerald