Request: Configure animations/durations

[JadElClemens]

imo, the current animation for moving items up/down the list is very very slow and overly dramatic for the action. I would like to propose a configurable animation duration at least, and maybe configurable animation for this action.

I have implemented a proof of concept with a static duration in #166 - I'm not so good with web languages/frameworks so if anyone has some input on how we may add this as a configuration (environment for now, until there is a configuration page) and grab it dynamically. My guess is we would probably need to implement that outside of static.

This request may be invalidated by #65, though I feel that drag+drop and buttons can both be useful in their own way(s), even together.