If replying to a message in a virtual folder, use the real folder as default

Add menuitem for 'last used folder' to the selectors

The accesskeys for default folder, no copy and last used folder are now options

- The pre-sent selector now automatically opens, if it gets focus (mainly after using access key)
- add menuitem for the current folder in the pre-sent selector
- add access key for 'No copy' in the selectors
- fix small bug in the copies-and-folder preferences window

added some missing localized strings

- use 'Sent'-folder as default if current folder is a special folder (Trash, Draft, Junk, Queue, Template)
- now should work in offline mode
- added options for 'what should be the default folder' (current or "Sent")
- added option to treat 'No Copy' as 'Copy to trash'
- Allows to choose the folder after sending (global option)
- Move folder selector to below the subject
- Fixed bug where messages saved as draft or template are additionally copied to the sent-folder
- Fixed a bug with the selector not accepting the selection

- Added option to additionally save a copy in the sent-folder
- Added some buttons/menuentries/keyboardshortcuts

fix a bug with the accountsettings for movemail-accounts

permits to choose any folder (with the current folder as default) at the time, the message is sent

- fixed bug with multiple identities per account
- fixed issue with folders marked as 'Sent'-folders and therefore couldn't be deleted afterwards (but see the FAQ on the homepage)