Specifically:
- Fixed ctz on 32-bit arm (where `uint64_t` is `unsigned long long`)
- Fixed build of random_cpp11 snippet when C++11 is disabled
- Updated CI scripts to run windows on push, and added a no-c++11 test
Ancient versions of CMake required else(), endif(), and similar block
termination commands to have arguments matching the command starting the block.
This is no longer the preferred style.
