Feature: export csv of attachments, emails

[supersexy]

This corresponds to my previous feature request, but may be a separate feature, so one more issue / feature request.

Additionally to saving attachments of many emails it would be of great value to have a csv file generated with all the meta information for each email with attachments. The csv file columns could look like this:

email id, email date, email subject, email from, email to, custom header x, number of attachments, attachment x size, attachement x name

Please note that multiple attachments in one email should be handled as one new row for each single attachment in that csv, so that we have one row for each attachment - it will be easy to extract all attachment info for one email via the email id, but it would be horrible to have multiple attachment information in a single row with changing number of attachments.

It would be great if one could define one or more custom header columns that will only be filled if that custom header matches headers contained in the email, otherwise just be ignored.

I guess such a csv feature will allow for a lot of use cases for professional mail handling.

[RealRaven2000]

Just consolidating all bugs that deal with attachments - this is a very special request, but there is not much of a chance that it gets implemented unless some more users want it as well, please check out other issues that have the attachments label - we have to fix a few of these first. Leaving this one open for later.