utils/shfmt.sh: implement checkers for forbidden styles
utils/shfmt.sh: implement checkers for forbidden styles

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