Add mobile menu and some minor changes
	modified:   README.md
	modified:   assets/css/default.css
	modified:   assets/css/desktop.css
	modified:   assets/css/mobile.css
	new file:   assets/images/icon-menu.png
	modified:   index.hbs
	modified:   partials/links.hbs
	modified:   partials/socialLinks.hbs
	modified:   post.hbs
	modified:   preview.jpg