Minor client fixes and refactoring
[client] refactoring and code cleanup
[Server] actually working send & drafts
@TODO : need tests
[Server] fix threading algorithm
[Server] clean up ugly comment
[Server] monkeypatch mailparser to tolerate malformed format=flowed email
[Server] fetch few mails from all boxes before fetching all
[Mixed] add icons for special use boxes
[Client] rename file-picker & use valueLink
[Client] factor mails_input widget
[Client] group all reply-making code
[Client] change components to take more id and less objects
[client] fix what i just broke with file_picker
[Client] open Draft message in a compose view, handle changes to message after send
[Client] "fix" json-patch for move to trash
[Client] add compose/messageID param (edit message)
[testfix] we now try to fetch a few mails before the big fetch