bringing back the lost per-project cmake executable setting

[René J.V. Bertin]

On Saturday September 16 2017 15:52:57 Morten Volden wrote:

> Wasn't sure why the per project option was removed in the first place, and
> I didn't need it. Therefore, I did not include it.

Fair enough. If memory serves me well I didn't implement it initially either, but was asked (or strongly suggested) to do so.
It turns out I do use it; saves some hassle when creating a new project with specific requirement, instead of importing an already pre-configured project.

Cheers,

R.