Fix CT::Vector

- change default paramter of CT::Int
- remove code duplication for CT::min, CT::mul, CT::add, CT::volume  and CT::Dot
- add new operation CT:min
- solve copy past bug that all operations only call mpl::plus

**Test:**
- [x] KHI Heating tests
- [x] memory race checks with cuda-memcheck
- [x] memory leak checks with cuda-memcheck