v1.1.0

• Thanks to A.Zulli the UNSELECT IMAP command of rfc3691 is now supported with ImapClient.unselectMailbox().
• Support THREAD IMAP Extension with ImapClient.threadMessages() and uidThreadMessage() as well as the high level API MailClient.fetchThreads() and fetchThreadData(), the latter can set the MimeMessage.threadSequence automatically. #44
• Access embedded message/rfc822 messages using mimePart.decodeContentMessage(). #138
• Added SearchQueryType.toOrFrom to easily search for recipients or senders of a message.
• All Mailbox commands now return the mailbox in question, not the currently selected mailbox.
• Improve automatic reconnects in high level MailClient API.
• Added high level OAuth login option and MailAccount.fromDiscoveredSettingsWithAuth() for easy setup. #137
• Appending a message will now return the new UID of that message.
• Continue editing a draft easily by calling MessageBuilder prepareFromDraft(MimeMessage draft).
• You now easier load the next page of of search using MailClient.searchMessagesNextPage(MailSearchResult).
• Improve null-safety.
• Breaking API changes:
  • To align with Dart APIs, MessageSequence.isEmpty and isNotEmpty are now getters and not methods anymore. So instead of if (sequence.isEmpty()) please now use if (sequence.isEmpty), etc.
  • Date headers are always decoded to local time. Instead of mimeMessage.decodeDate().toLocal() now just call mimeMessage.decodeDate().
  • High level API MailSearchResult has been refactored to use PagedMessageSequence.