[Drip] New registration python scripts

[Robert Moskowitz <[e-mail]>]

https://github.com/ietf-wg-drip/drip-scripts

2 new scripts:

csr-gen.py
hda-endorse.py

Adam, Stu, and I have been working on a revised flow for the UA 
registration into the USS/HDA.

We are using X.509 objects under the DRIP DETs and Endorsements.

So the UA has limited info about itself.  It creates a very minimum 
CSR:  UA SerialNumber and EdDSA25519 keypair.

This CSR gets set (through some magic) to the GCS.

Adam is defining all that will go into the GCS to USS to HDA flow.

The HDA creates the DET (It knows the proper RAA and HDA values), 
Endorses it, creates a DRIP-lite X.509 cert, and stores all this in DNS 
and sends it back to the USS that sends it back to the GCS, that sends 
some of it to the UA.

Well there is more, but the scripts are pretty much working.  Still need 
to do some fixing to hda-endorse.py (X.509 dates are not right).

But I just wanted to hit a milestone on this part of the registration 
work.  Now I have to read through Adam's updated text, add my part now 
that I have scripts, and we can update drafts.

We HAVE been busy.

Bob