Install the Latest GitFlow Version on macOS

Issue:

When you install the default GitFlow version via brew, an extremely outdated version (over 10 years old) is installed.

Solution:

Check your installed GitFlow version:
git-flow version
If you already have GitFlow installed, you must first uninstall the old version: 
brew unlink git-flow
Then, you need to add a tap in brew to access the current version: 
brew tap CJ-Systems/homebrew-gitflow-cjs
Finally, you can install the latest git-flow version:
brew install git-flow-cjs