Add 'gists/sizeof/' from commit '531e6189873474736610f3f5abc975db8214ded5'

git-subtree-dir: gists/sizeof
git-subtree-mainline: 91f213d546540d981cfd25ce6f1fe2da0c32160a
git-subtree-split: 531e6189873474736610f3f5abc975db8214ded5
Remove from utils and added as a subtree from a Git Gist.
Move to using subtree for sizeof Gist
Exporting to Node and the Browser