Remove/archive 8.x-1.x and start over, bringing in only newly ported or created modules

We already have an 8.x-1.x branch, but it has only been inactively maintained (7.x-1.x patches have been cherry picked onto it). However, it hasn't passed tests for 6 months (theming and render, contextual links).

The lack of maintainer attention to solve those has put the entire branch into bad shape, and probably some 7.x cherry picks have been missed. *And* some people would like to start writing examples that demonstrate new features. But without testing working it's a pretty shady deal.

in #1516840: Get more active maintainers and allow a greater diversity of examples I was trying to solve two things, first this issue, and second the distribution of ownership. But it looks like that one may not fly.

So here I recommend that we archive the 8.x-1.x branch (Copy it, empty it) and then start to add to it *only* new examples or examples that have explicitly been ported from 7.x because somebody wanted them. This avoids the whole chase-head-just-because problem in the 8.x cycle.