They changed the token behind the "ETH" symbol! ETH/USDC now means something different! I'm sure they had a good reason but I'm reverting this until there's a better fix.
This reverts commit 5caf8482ce.
* Extended mechanism for combining instructions.
* Fixed Account's calculations of deposits and borrows.
* Added net_assets to Account.
* Groups now maintain loaded RootBanks, not just PublicKeys of them.
* Fixed simple market-maker's calculation of position sizes.