Add test of different wayes of implementing ints with ?-Int

Curretly we only test addition. There are two implementations one that uses two cmoves and ints
and another that uses doubles and nan. Doubles seems to win but not by a lot
Make int-speed-test less over-optimizable by using std::shuffle, now it seems that doubels are more then 3 times faster
Improve tests
Fix smome small issues
Better if codegen