Migrate to Solidity

[HardlyDifficult]

• [x] Whitelist
• [x] BigMath
  • [x] bigDiv
  • [x] sqrt
  • [x] copy into this repo for the audit
• [x] DAT
  • [x] SafeMath
  • [x] OZ token
• [x] Update ZOS
  • [x] Address.sendValue
• [x] Update hd-eth-contracts
• [x] Code coverage
  • [x] enabled
  • [x] report
  • [x] 100%
    • [x] BigDiv
    • [x] Sqrt
    • [x] DAT
• [x] Solidity lint (CI enforced)
• [x] MythX (just false positives it seems)
• [x] Slither (failing to run...)
• [x] ERC-20 tests
• [x] SmartDec
  • [x] BigDiv
  • [x] Sqrt
  • [x] Dat
• [x] review unsafe math again after everything else is done

Redeploy

• [x] c-org-abi
  • [x] test contracts
• [x] hardlydifficult-test-helpers
• [x] c-org-js
  • [x] Update to support port
  • [x] Gas reporter
    • [x] enabled
    • [x] report
    • [x] js constants
  • [x] add EthToUSD (via uniswap eth -> usdc)
• [x] Faucet (admin account mismatch)
• [x] Admin site
• [x] Verify contracts

Other

• [x] post vyper contracts
• [x] update Dune queries (maybe backup first)

[HardlyDifficult]

Pending re-deploy after audit updates