Headers, formatting, minor refactor.
Split 'common/' into commit '1564d875739aa9c0bdedab5baf1b902117007743'

git-subtree-dir: common
git-subtree-mainline: a48c2ebb53dbdc97502e774cdd0f581e916c7e81
git-subtree-split: 1564d875739aa9c0bdedab5baf1b902117007743