Add contact field to recognizer registry

[atruskie]

We'd prefer the reocgnizer registry to always point to a public URL where a user can get the recognizer.

However @KellieVella pointed out this might not always work, and we should add an alternative contact option. Email might work but I generally prefer not adding emails to public sites... so maybe just a free form field

• Add contact field to registry schema
• render contact field on registry page

[atruskie]

This might also be reframed as series of contact methods. E.g. github url, organization page, twitter handle, orcid, etc...