feature: Add gravatar like endpoint

[pke]

This idea to fetch gists is genius (at least for us techies that have a github repo)!

How about making the registry more accessible by additionally allowing a gravatar like request endpoint.
Initially it could also use MD5 for reasons to look similar to gravatar, however I'd favour SHA256 (significant 7 chars maybe only).

Request	Response
GET /resume/<email-hash>[.json]	resume.json
GET /resume/<email-hash>.html?theme=	same as registry today returns
GET /resume/<email-hash>.qr	SVG QR-Code for use in img tags
GET /resume/<email-hash>.md	Markdown rendition

[thomasdavis]

The old hosting use to support this, let's bring it back, labelled as high priority.

I imagine that qr should just link to the registry hosted url?

[pke]

I imagine that qr should just link to the registry hosted url?

yeah, why not.

[thomasdavis]

Initial work on qr code -> https://registry.jsonresume.org/qr/thomasdavis

Will change it over to .qr first chance I get

[pke]

works as intended! ;) Great.

[thomasdavis]

It feels a bit weird using .qr then returning an image, how about registry.jsonresume.org/username.qr.png?

[thomasdavis]

Updated to .qr.png format and added to https://jsonresume.org/getting-started/