abandoned feedstocks?

### Your question:

I have a concern that certain feedstocks have not been able to keepup with certain migrations for quite some time.

It feels like we should be able to tag certain repos, maybe simply "archiving them" could help the bots complete migrations so that the global pinning can be updated.

Not to point fingers (I know priorities change) but feedstocks that come to mind are:
* [ ] https://github.com/conda-forge/trilinos-feedstock/pulls
* [ ] https://github.com/conda-forge/pytrilinos-feedstock/pulls
* [x] https://github.com/conda-forge/shogun-cpp-feedstock/pulls
* [x] https://github.com/conda-forge/caffe-feedstock/pulls <-- This one should probably be archived.
* [x] https://github.com/conda-forge/libcugraph-feedstock
* [ ] ~~https://github.com/conda-forge/colored-feedstock~~
* [ ] https://github.com/conda-forge/dioptas-feedstock
* [ ] https://github.com/conda-forge/lxqt-build-tools-feedstock
* [ ] https://github.com/conda-forge/kaolin-feedstock
* [ ] https://github.com/conda-forge/pyne-feedstock/pulls
* [ ] https://github.com/conda-forge/cyclus-feedstock/pulls

Generally, making it clear that they are no-longer maintained may encourage others to maintain the recipes.

Edit: changed a word from "feedstock" to migrations"