[client] fix placeholder to be correct ports
Manage mailboxes
Improve UX of mailboxes management
[Mixed] Improve error handling & Promise code style
[Server] Add functions to properly destroy an account & improve comments
[Client] Improve first login flow (Create account -> mailbox)
[Client] add component ToastContainer (wip) & fix progress styles
[Client] move the topbar from the application
[Client] improve menu in no-account mode
Merge commit '31cea0c3a7433ddf2da1fe54896fc7617cc6d175'

Conflicts:
	client/app/components/account-config.coffee
[Client] fix topbar mailboxes
[Server] Add mailbox management & safe deletion processes