DKIM properties:
- messages not signed
- messages signed by the From: domain
- messages signed by a parent domain
- messages signed by some other domain

SPF properties:
- no "pass"
- "pass" for From: domain
- "pass" for parent of From: domain
- "pass" for some other domain

Organizational Domain computation:
- various test cases (.com, .org.uk, etc.)

DMARC policies, mixed with each of the above groupings:
- p=none
- p=quarantine
- p=reject
- sp=none
- sp=quarantine
- sp=reject
- use "reject" and set "pct" to some value, ensure rejected message count is
  in that ballpark

REPORTING:
- ensure correct output for each case above when HistoryFile is set
