Bcloud

* Fixed: failed to get bdstoken (pull214, by zhaihj).

* Fixed: failed to sign in (pull177, by mhohai).

* Fixed: margin_left is deprecated in gtk3.12
* Fixed; shrink left side panel
* Fixed: ConfirmDialog does not exists

* i18n updated
* Redesign Preferences dialog
* Update contributor list
* Fixed: syntax error
* Support shutdown system automatically
* Fixed: State has no attribute `DOWNLOADED`
* Support sync dir

* Add `display-avatar` option
* App logo updated
* i18n updated
* Fixed: Gtk.Button.new_from_icon_name() requires two parameters;
* Fixed: kb -> kB

* Fixed: KeyError in SigninDialog
* Fixed: TypeError, string indices must be integers in SigninDialog