Add permalinks

For now, these are only for posts with titles, but that will change.

go/blog/blog.go

article h1 {
	margin: 0;
	margin-right: 1em;
}
article header .permalink {
	margin-left: 0.1em;
	text-decoration: none;
	color: #555;
	visibility: hidden;
}
article header:hover .permalink {
	visibility: visible;
}
article time {
	margin-left: 1em;
	color: #666;
}
<article id="{{ .Id }}" class="shell">
	<header>
		<h1><code class="language-shell">{{ .Title }}</code></h1>
		<a class="permalink" href="#{{ .Id }}">∞</a>
		{{- if .Date }}<time>{{ .Date }}</time>{{ end -}}
	</header>
	{{- if .Content }}
<article id="{{ .Id }}" class="link">
	<header>
		<h1><a href="{{ .URL }}">{{ .Title }}</a></h1>
		<a class="permalink" href="#{{ .Id }}">∞</a>
		{{- if .Date }}<time>{{ .Date }}</time>{{ end -}}
	</header>
	{{- if .Content }}
	{{- if .Title }}
	<header>
		<h1>{{ .Title }}</h1>
		<a class="permalink" href="#{{ .Id }}">∞</a>
		{{- if .Date }}<time>{{ .Date }}</time>{{ end -}}
	</header>
	{{- end }}
	{{- if .Title }}
	<header>
		<h1>{{ .Title }}</h1>
		<a class="permalink" href="#{{ .Id }}">∞</a>
		{{- if .Date }}<time>{{ .Date }}</time>{{ end -}}
	</header>
	{{- end }}
<article id="{{ .Id }}" class="text">
	<header>
		<h1>{{ .Title }}</h1>
		<a class="permalink" href="#{{ .Id }}">∞</a>
		{{- if .Date }}<time>{{ .Date }}</time>{{ end -}}
	</header>
	{{- if .Content }}
	{{- if .Title }}
	<header>
		<h1>{{ .Title }}</h1>
		<a class="permalink" href="#{{ .Id }}">∞</a>
		{{- if .Date }}<time>{{ .Date }}</time>{{ end -}}
	</header>
	{{- end }}