Improvements
* Grand central(3.0.1) node update by eric-volz in https://github.com/eric-volz/DefichainPython/pull/62
* Python 3.6 is no longer supported by [tests](https://github.com/eric-volz/DefichainPython/actions/workflows/tests.yml)
[The Code base to this release](https://github.com/eric-volz/DefichainPython/tree/ef66e33d4e1089d0d0aa84e24e30b603b117d10d)