Finish head attribute settings.

- Add open graph meta attribute (also with twitter card, google puls, facebook)
- Split the modules with css, icon, open graph etc.

layouts/partials/head/open_graph.html

@@ -0,0 +1,33 @@
+{{- $Site := .Site -}}
+{{- $Params := .Site.Params -}}
+{{- $Page := .Page -}}
+{{- with .Site.Params.openGraph -}}
+{{- if .enable -}}
+{{- $langCode := replaceRE "-([a-z]+)" (upper (substr $Site.Language -3)) $Site.Language }}
+  <meta property="og:type" content="website">
+  <meta property="og:title" content="{{ $Page.Title }}">
+  <meta property="og:description" content="{{ default $Params.description $Page.Description }}">
+  <meta property="og:image" content="{{ default $Params.customLogo.url }}">
+  <meta property="og:url" content="{{ $Page.Permalink }}">
+  <meta property="og:site_name" content="{{ $Site.Title }}">
+  <meta property="og:locale" content="{{ $langCode }}">
+  <meta property="article:author" content="{{ default $Params.author $Page.Params.Author }}">
+
+{{- with .twitter -}}
+{{- range $attr, $val := . }}
+  <meta name="twitter:{{ $attr }}" content="{{ $val }}">
+{{- end -}}
+{{- end -}}
+
+{{- with .googlePlus }}
+  <link rel="publisher" href=" {{ . }}">
+{{- end -}}
+
+{{- with .facebook -}}
+{{- range $attr, $val := . }}
+  <meta property="fb:{{ $attr }}" content="{{ $val }}">
+{{- end -}}
+{{- end -}}
+
+{{- end -}}
+{{- end -}}