Vulnerabilities in hardware and software.

[bmmcwhirt]

Please see pull request for details: Added security warring, and forced cryptography==37.0.4. #106

The change will allow users to follow the Blinky-Hello-World tutorial, but the software, cryptography 37.0.4 and the hardware ATECC608A both are vulnerable to attacks. If you decide to continue to use this device PLEASE make sure you are using a hardware MFA token like Yubikey for your AWS account.