trigger rebuilds automatically when twoliter has a breaking change #215
Description
We need a way to trigger a rebuild (instead of incremental builds) when something fundamental about Twoliter requires it.
Proposal: BUILDSYS_EPOCH environment variable that is watched by all build types (except Repack?).
Definition of done, we have a way to force a rebuild of all the Cargo packages when Twoliter has a breaking change requiring it (like it does in #210)