Update validators (other actions) from successful election

[ethanfrey]

We need to perform a number of actions based on election results (governance).

These will include updating the validator set and updating fee distributions among, as well as likely updating the enabled schema (on chain code upgrade). We need a general framework to do so, ideally without importing those modules from x/gov, nor importing x/gov from these, but some sort of app-level registry.

I will make a spike in the next day or two to demo one approach. Happy to see other ideas how to do so (simple spikes first, then we decide on direction to develop)