RC7

Release with the fixes to the C4 audit

• Check seriesId, ilkId, and vaultId can't be zero
• Random vault ids
• Block stir to the same address
• Replace public auth with external auth
• Make JoinFactory use CREATE and wand.addAsset deploys the Join
• Only receive Ether from WETH
• PoolRouter.batch returns the return values of the batch actions
• Check for function signature collisions in CI

Full list