[dev] Refactoring: Now messages only in msg spool would be decrypted; those in other spools are assumed being already decrypted (or failing decription).  Exception is "outgoing" (archive) spool: It may contain original messages if archive_crypted_msg parameter is "original"; also, wwsympa::do_send_me() and List::archive_send_last() should decrypt messages before sending them.
As a side effect, Message->new() no longer takes noxsympato parameter.  Now messages are always stored into spools in "serialized" form (with prepended X-Sympa-*: pseudo-header fields) and deserialized by Message->new().

Issue: Is it allowable that decrypted messages are stored into spools?


git-svn-id: https://subversion.renater.fr/sympa/branches/sympa-6.2-branch@11238 05aa8bb8-cd2b-0410-b1d7-8918dfa770ce