Remove v6 and backwards compatibility with GOV.UK Elements

[fofr]

Remove v6 backwards compatibility with GOV.UK Elements. GOV.UK Elements is deprecated and has not been released since July 2018. New prototypes should be using the GOV.UK Design System.

[paulrobertlloyd]

Love this! I delete these things every time I start a new prototype.

[joelanman]

this is something I've considered, is it causing any issues other than downloading code you don't need?

[fofr]

From a x-gov Slack thread:

It’s more of a question of – why is it still here – why is the use of deprecated packages like elements and toolkit still being supported?

I think the crossover of users pulling the latest kit to update their prototypes and users still stuck on elements is going to be tiny.

Also, the upgrade path for a prototype created from a ZIP file is usually updating the dependencies in package.json, rather than re-applying commits from the base repo.

[joelanman]

Thanks for this. Unfortunately this is not a priority for us at the moment. We do want to look into tidying up the kit and removing things people don't need as a body of work, but it's not our focus at the moment. When we do it we'd need to check who is affected and how to communicate the changes to them.