Add possibility to alternate between dim up and down by button hold actions

Is your feature request related to a problem? Please describe.
I would like to be able to control both on/off and dim of a lamp using a single button.

Describe the solution you'd like
Let's say I have a single button remote which supports short press and hold actions. I would like to be able to both toggle on/off of a lamp using short press of the button, but also be able to dim the same lamp up and down but using the hold action. The hold action should alternate between dim up and dim down. The speed of dimming should preferably be controllable via config. The dimming should occur as long as I hold the button, and stop once i release the button.

Describe alternatives you've considered
Currently I'm solving this by using ControllerX via Appdaemon, but would like to move this logic into z2m to get rid of the dependency to external applications.

Additional context
Thanks for the great extension :)