export recipients, allow re-import

[emhl]

Currently the export form doesn't export the recipients and the import doesn't allow import of the alias list from another instance without manual modifications because the columns are named differently.

It would be nice to update both forms to make it easier to move your aliases. Maybe even with the stats for each alias.

Additionally, i think it would be fine to not export the ids and aliasable_type column. if someone needs that data, they are probably already using the API to get it. the extension column is completely empty for me as well. what info should be presented here?