HAPI extra code support RFC

[lp]

HAPI supports a limited sets of code system. Lets find the path forward to integrate more.

Write a RFC to answer the following questions:

• what code systems are supported, what extra code systems do we need to support?
• what universal mechanism could be used to ingest the extra codes

Timebox: 16h

Output: A RFC entry within this GH project's wiki

[biximilien]

See Extra Code Support RFC

[biximilien]

Related #22

[biximilien]

Proof of Concept implementation #26