Blockchain Walkthrough

This code was covered in "Python Tutorial: Build A Blockchain In < 60 Lines of Code"

https://medium.com/@michaelchrupcala/python-tutorial-build-a-blockchain-713c706f6531

changes since forking:

• Flask is used to enable interaction through http. 'GET /chain' is implemented for illustration
  • install dep first, 'pip install -r requirement.txt'