add arm and PPC verification tests using qemu

[thirtytwobits]

https://www.qemu.org/docs/master/system/target-arm.html

• [ ] Install qemu-arm and qemu-ppc on our docker build container
• [ ] install cross-compilation toolchain for arm into our build container (probably gcc-arm-linux-gnueabihf)
• [ ] install cross-compilation toolchain for ppc into our build container
• [ ] Add arm and ppc build targets to our cmake build
• [ ] Add qemu test running utility to our cmake build (e.g. qemu-arm -L /usr/arm-linux-gnueabihf arm_test)