Handling of missing mime downloads and mail processed messages.

Wino.Core.Domain/Translations/en_US/resources.json

@@ -112,6 +112,7 @@
     "DiscordChannelDisclaimerMessage": "Wino doesn't have it's own Discord server, but special 'wino-mail' channel is hosted at 'Developer Sanctuary' server.\nTo get the updates about Wino please join Developer Sanctuary server and follow 'wino-mail' channel under 'Community Projects'\n\nYou will be directed to server URL since Discord doesn't support channel invites.",
     "DiscordChannelDisclaimerTitle": "Important Discord Information",
     "Draft": "Draft",
+    "Busy": "Busy",
     "EditorToolbarOption_Draw": "Draw",
     "EditorToolbarOption_Format": "Format",
     "EditorToolbarOption_Insert": "Insert",
@@ -123,6 +124,7 @@
     "ElementTheme_Light": "Light mode",
     "Emoji": "Emoji",
     "Exception_WinoServerException": "Wino server failed.",
+    "Exception_MailProcessing": "This mail is still being processed. Please try again after few seconds.",
     "Exception_ImapAutoDiscoveryFailed": "Couldn't find mailbox settings.",
     "Exception_ImapClientPoolFailed": "IMAP Client Pool failed.",
     "Exception_AuthenticationCanceled": "Authentication canceled",