Add outbreak schema and populate with initial outbreaks info

[NoopDog]

Need

See parent ticket #200

Approach

1. Add a LinkML schema for outbreaks
2. Add an outbreak.yaml with the content from the Official List of Outbreaks from NIAID
3. We initially said outbreaks would have a list of resources (URLs to external sites). Where would we find these?
4. Create the validator for the outbreak.yaml.
5. Generate an outbreaks.json with any additional fields e.g., scientific name, common name from the organism.json

Starter Input Schema

• Taxid
• Priority (highest, Critical, High, Moderate-High, Moderate
• Description - this may need to point to a markdown file
• Resources (array of title, URL)

outbraks.json schema

(no formal schema)

• Add common name