[Cmake] headers in project files?

[Klaas Holwerda]

Hi,

Is it possible to have a folder ( next to the source file folder) in the 
project files which contains the header files.
This is very common in other (open source) projects, but more important, 
it is very handy.

I am rather new to cmake, so maybe it is simple to do,
but i don't see how,

Thanks,

Klaas