Release Beta 2.27

[Stefan Selbitschka]

Hi,

I just uploaded a new beta release, which include the following improvements:
- IMAP mailbox / folder list should now be complete again
- text/calendar is shown correctly again
- Option "write PGP files" in certificate store to fix corrupted pgp file stores
- PGP key import of multiple key is now faster
- Implementation of "memory hole" => PGP protected headers (for more info see http://modernpgp.org/memoryhole/)

About Memory Hole:
===============
During the last Open PGP E-Mail Summits a concept for protecting email headers in PGP encrypted messages was created. The idea is to protect headers like subject, message-id, reply-to, ... which are leaking meta data. R2Mail2 supports now sending and receiving memory hole protected messages. Since this standard is not wide spread at the moment you need to enable this feature in security setting for sending. More information can be found at http://modernpgp.org/memoryhole/.

regards
stefan