Request ORCID credentials

I am working on code for securely acquiring user's ORCID (from https://orcid.org) to associate a GitHub user's account to an ORCID account.

ORCID is a global ID of a scientist.

It is useful for:
- an addiitional Anti-sybil measure
- paying scientists compensation from a compensation fund (to be added in the future) based on the number of their publications associated with this ORDID.

Things to do:
- [Register](https://info.orcid.org/register-a-client-application-production-member-api/) GitCoin as a member of ORCID, secretly store the client ID and client secret they will provide you.
- Create also the sandbox credentials, publish the sandbox credentials in a response to this issue.