Add License headers to cmake code
According to the KDE licensing policy, cmake code should be licensed as BSD-2-Clause.
I need approvals for this from @carlschwan, @nicolasfella and @adridg
Edited by Tobias Fella
According to the KDE licensing policy, cmake code should be licensed as BSD-2-Clause.
I need approvals for this from @carlschwan, @nicolasfella and @adridg