Remove unused images

[anbraten]

Moved unused images to docs/unused-images/ so translators do not translate / update images that aren't used at all. It will also speed up the crowdin sync drastically if we don't upload those files.

[anbraten]

As it includes #2011 we need to merge that one first.

[peterleimbach]

@anbraten Thank you. But why not just delete them?

[anbraten]

@peterleimbach We can also delete them.

[psonnera]

@anbraten can you check the list is still up to date? This would be a good idea to get rid of them indeed,

[anbraten]

@psonnera Sure, I will check the list again and update tonight if necessary

[anbraten]

I've checked again and removed one new unused image.

[psonnera]

Merged images deletion but reverted https://github.com/openaps/AndroidAPSdocs/pull/2012/commits/f561a132cd6f51bed554ea329806b0887cc26456