Latest version of find_nearest and find_nearest_if has been commited

[Sylvain Bougerel]

Hi everyone,

I just commited the latest version of the library! Please get the full
new tree from the GIT archive. For those who do not have the git
suite, I'll send you tarball on a per-request basis.

I consider this expermiental as long as everyone hasn't agree that
it's good for the next tarball release.

Please read the ChangeLog! There quite a lot of modif. Paul, I was
foolish to think about removing the find_nearest_if(). They now
benefit from the new algorithm too.

Only find_exact() still uses the old algorithm. The reason for this is
that I have to write yet another piece of code. That's what I will do
next.

On Friday evening, I found yet another improvement to the algorithm.
It increased the speed by another 3-4%. (When it do distance
calculation, instead of accumulating the distance of all the elements
each time, it stops accumulating the distance of the elements as soon
as it is worse than the best found)

Could someone compare the performance of find_nearest with ANN? Just
to see how it fares now?

Enjoy,

- Sylvain