Choose a different mail header date, since 1970... is default for DateTime and datetime (test results are nearly useless).
Add IDocumentMetadata behavior to ftw.mail.mail
Initialize metadata on mail.
Fill document_author metadata with fullname queried by email address (OGDS).
Upgrade step: initialize metadata on extisting mail instances
Init missing field values in existing mails. Test metadata upgrade step.
Implement setting default values for mail metadata.
Remove specific mail index methods (document_date, document_author, receipt_date, sortable_author).
Move title and message into the common fieldset / Move title at first position.
Refactor mail metadata tests.
OGQuickUploadCapableFileFactory: Set default values before adding content to container.

(Prevents values set by handlers on ObjectAddedEvent to be overwritten again).
Merge pull request #312 from 4teamwork/mle-public_trial_init_metadata_mail

Map E-Mail headers to Document metadata and set defaults
Add classification behavior to mails.