FAQ: document `HOMEBREW_NO_CLEANUP_FORMULAE`
FAQ: document `HOMEBREW_NO_CLEANUP_FORMULAE`

nandub/brew,JCount/brew,nandub/brew,JCount/brew,nandub/brew,MikeMcQuaid/brew,Homebrew/brew,MikeMcQuaid/brew,Homebrew/brew,Homebrew/brew,nandub/brew,MikeMcQuaid/brew,JCount/brew,JCount/brew,MikeMcQuaid/brew,Homebrew/brew