Squashed 'blocks/simple_clock/' content from commit 18a3206

git-subtree-dir: blocks/simple_clock
git-subtree-split: 18a3206c6e641a454824004f1cbd2002741bfe86
Merge commit '26b40c2e6bef87525da857f61ef52306cf2ca212' as 'blocks/simple_clock'