Establish a repository of "test cards"

[kpshek]

From @jmandel on March 17, 2016 15:53

These can live in a standalone github repo, and should include "valid but tricky" cards with:

• missing optional fields (to test default/formatting logic)
• overly long data (to test truncation)
• combinations of information, suggestions, and app links
• attempts to inject HTML into the target page (XSS)
• multiple buttons
• multiple links

And also should include invalid cards, with:

• invalid JSON payloads (un-parseable)
• missing required fields
• multiple values for a field that allows only one value

Copied from original issue: cds-hooks/cds-hooks#4