Update mythril to 0.20.4

Update version to 0.20.3

Update to 0.20.2

Update version to v0.20.1

Merge pull request Consensys#905 from ConsenSys/update-version

Update version to 0.20.0

update to version v0.19.11

Update version v0.19.10

version update

Update version.py

Merge pull request Consensys#724 from ConsenSys/develop

Update version.py