Redesign the post meta layout

- posted date
- updated date
- read time
- license statement of post bottom
- also refactor the `timeago.js`

_includes/timeago.html

@@ -1,27 +1,26 @@
 <!--
   Date format snippet
-  See: /assets/js/_utils/timeage.js
+  See: ${JS_ROOT}/utils/timeago.js
 -->
 
 {% assign tooltip_df = site.data.locales[lang].date_format.tooltip %}
 {% assign post_long_df = site.data.locales[lang].date_format.post.long %}
 {% assign post_short_df = site.data.locales[lang].date_format.post.short %}
 
-{% if include.preposition %}
-  {{ include.preposition }}
-{% endif %}
-<span class="timeago {% if include.class %}{{ include.class }}{% endif %}"
-  {% if include.tooltip %}
-    data-toggle="tooltip"
-    data-placement="bottom"
-    title="{{ include.date | date: tooltip_df }}"
-  {% endif %}>
+<em class="timeago{% if include.class %} {{ include.class }}{% endif %}"
+    date="{{ include.date }}"
+    {% if include.tooltip %}
+      data-toggle="tooltip"
+      data-placement="bottom"
+      title="{{ include.date | date: tooltip_df }}"
+    {% endif %}>
+
   {%- assign this_year = site.time | date: "%Y" -%}
   {%- assign post_year = include.date | date: "%Y" -%}
+
   {%- if post_year == this_year -%}
     {{ include.date | date: post_short_df }}
   {%- else -%}
     {{ include.date | date: post_long_df }}
   {%- endif -%}
-  <i class="unloaded">{{ include.date | date_to_xmlschema }}</i>
-</span>
+</em>