tradfri-cli as global executable npm module

[MDecker-MobileComputing]

It would be convenient if tradfri-cli could be installed as global npm package (i.e. npm install -g tradfri-cli), so that is can be used on the command line in every folder on the machine.

Examples for how the global execution of a global tradfri-cli could look like:

tradfri-cli devices
tradfri-cli change "Bulb 1" --on --color efd275
tradfri-cli scenes
tradfri-cli scene "Room 1" my_scene

In this article it is described how to implement an npm package which a global executable script.