Hammerspoon: use the keyboard shortcuts to launch Apps

We can use command + tab to switch between opened apps, but it may require multiple strokes, also the list only contains opened apps.

With the below Hammerspoon settings, we can use shortcuts to launch/switch apps EVEN the app is not launched yet.

• option + shift + c to launch Visual Studio Code
• option + shift + s to launch slack
• option + shift + T to launch iTerm