[Enhancement] Useful wrappers for common operations

[robertodr]

The file psi4OptionsTools.cmake within the Psi4 project defines several general-purpose wrappers for common CMake operations. Possibly consider incorporating those in Autocmake?

[bast]

Thanks! These look very useful but we need to make sure that this is OK license and copyright-wise. Unfortunately we cannot take GPL code into BSD without asking.

[robertodr]

Yeah, sure. I forgot to add that to the description!

[bast]

We might also discuss whether BSD is good for us. But that is for another thread.