Fixes #104

Solves #95

Solves #95

Add options to also archive

• trash folders
• junk folders
• outbox folders
• draft folders
• template folders
• archive folders

Adds options to include special folders (like junk)

OWL support (see https://www.beonex.com/owl/ )

Remove experiment code
That means configuration of Thunderbird < 68 will no longer be converted.
Users that still run on old Thunderbird and migrate later must do the setup again.

With that change the addon need less permissions while installing it in Thunderbird.

compatability for Thunderbird 74
internal improvements

messages marked as non-junk were not archived

locale folders were not archived