Education resources

[cromewar]

This Pull adds Cyfrin Updraft to the Tutorials section; Updraft is growing to be the way-to-go platform to learn smart contract development and Security; the courses are 100% free and guided by industry-leading experts.

Checklist

• The URL is not already present in the list (check with CTRL/CMD+F in the raw markdown file).
• Each description starts with an uppercase character and ends with a period.
  Example: solc-js - JavaScript bindings for the compiler.
• Drop all A / An prefixes at the start of the description.
• Avoid using the word Solidity in the description.