[Cmake] subdirs please change it.

[klaas.holwerda]

Hi,

I like Cmake a lot, i use it in wxArt2D together with wxWidget.

But this strange behaviour when it comes to going into subdirs, after 
only the top level is done,
is becoming a nightmare!!
This makes it almost impossible to write something more modular.

And therefore is ask to please consider changing this in such a way that 
the CMakeLists.txt files
are processed sequential, and it goes into subdirs when they are 
encountered.

This subject is brought up before, so i think it is not needed to 
explain what are the problem with the current
approach. It comes down to setting variable at a  lower level in a 
subdirectory, which you want to use at the highest
level. But there it is not know yet, since the lower levels are not 
processed yet.
Very disturbing and unpredictable.

It is not exactly clear to me why it is like this ( soemthing witrh 
threads??), but i think that feature i would
prefer to give up, in order to make Cmake much easier to understand.

I hope you will consider this, since by feeling is that it makes CMake 
much easier to handle.

Thanks for Cmake and regards,

Klaas