blog: blog widget implementation: this patch implements a basic blog widget. The search bare can be used to change node (only node for now, will be improved to do search and all). Publication on current node can be done by pressing the pencil icon. A checkbox can be activated to use end-to-end encryption. No pagination or comments are supported for now. Due to lack of HTML rendering in Kivy, only simple formatting is supported. If item is end-2-end encrypted, a green closed locker is shown next to publication date. rel 380