Upgrade all casks. **Warning** Takes a while. Make sure you have stable internets.

cask-update

# Run "upcask" in the terminal and you can upgrade every cask you have installed. Run once a week.
function upcask () {
  for cask in `brew cask list`; do
    brew cask install $cask --force
  done

  # I use TotalFinder so I like to restart after an upgrade.
  open -a TotalFinder
}