go/fast tips being published

https://abseil.io/fast/ is external exposure of one of the projects I've been involved in at Google. For a long time I've felt that performance optimisation is the best job in the world, but to really move the needle we need to ensure that folks have access to information about writing efficient code - hence this blog and the books. At work, internally we've been gathering and documenting best practices for performance. Finally, we're able to publish some of these externally!