Upgrade: refactor states into separate contract

[shine2lay]

currently every contract has a version of states that it tracks internally, one possible improvement that we could make have a contract that holds states for different contracts similar to registry.

This would help with setting system wide states like "shutdown" and possibly system wide "system freeze" in the future.

[mrosendin]

Can call a single contract ("States" contract) and Probity will be in shutdown mode instead of calling 7 different contracts.