Replace disease_occurrence.status UNBATCHED with AWAITING_BATCHING
Log minimum data volume/spread messages as "error" so that they are e-mailed out
If we are in disease group setup and batching has started, points that are subsequently acquired are now given status AWAITING_BATCHING (rather than READY, which would send them to the model too early)
Split disease occurrence handling (model outputs) into two transactions: 1) the main handling 2) a clean-up process which ensures that any occurrences acquired during batching initialisation are themselves initialised
Fix checkstyle violations
Send e-mail upon minimum data volume/spread error
Fix checkstyle violation
Clarify comment
Fix following review
Merge pull request #297 from SEEG-Oxford/367-unbatched

Ensure occurrences that are automatically acquired during batching are in the correct status