UMIP173 -Approve DVM Upgrade to DVM 2.0

This UMIP proposes an upgrade to the UMA Data Verification Mechanism (DVM) that re-works core parts of UMA’s tokenomics.
At a high level, this upgrade adds a new staking and slashing mechanism wherein voters earn a pro-rata share of emissions
for staking and are slashed for voting wrong (or not voting). This upgrade also re-works a number of other DVM contracts
such as an updated governor, proposer contract and new designated voting contract. Finally, this upgrade has a new
emergency recovery mechanism to the DVM that enables emergency admin proposals to bypass the DVM’s schelling point
oracle system in the event of an emergency. More detail on the individual changes are broken down in the sections that
follow.