Proposal: Opt out of project/hw combination

[Uroc327]

AFAIK, it is only possible to opt out of projects at the moment. I think it could be a good idea to opt out of project/hardware combinations.

Apparently Milkyway@home and Einstein@home are having problems with OpenCL on amd on my machine. Their Nvidia and cpu tasks work fine though. Also other projects amd gpu tasks work fine.
In this case I would like my machine to keep working on M@h and E@h cpu and nvidia tasks and fetch amd tasks from different projects.