update header and description

Author: zerunniu

_config.yaml

@@ -1,7 +1,7 @@
 # site properties and page defaults
-# title: Distributed compUting, optimizAtion, and Learning (DUAL) group at USyd
+title: Distributed compUting, optimizAtion, and Learning (DUAL) group at USyd
 subtitle: Distributed compUting, optimizAtion, and Learning (DUAL) group at USyd
-description: please Input context
+description: Research group at the University of Sydney focusing on distributed computing, optimization, and machine learning.
 header: images/background.jpg
 footer: images/background.jpg
 proofer: false

_includes/header.html

@@ -28,7 +28,7 @@
     {% endif %}
     {% if site.logo-text != false %}
       <span class="title-text" data-tooltip="Home">
-        {% if site.title and site.show-title != false %}
+        {% if site.title and site.show-title != false and page.url != "/" %}
           <span class="title">{{ site.title }}</span>
         {% endif %}
         {% if site.subtitle and site.show-subtitle != false %}

_includes/meta.html

@@ -9,6 +9,10 @@
 
 {% assign title = title | xml_escape %}
 
+{% if title == nil or title == "" %}
+  {% assign title = site.title | xml_escape %}
+{% endif %}
+
 {% assign fulltitle = "" | split: "," %}
 {% if title and title != "" %}
   {% assign fulltitle = fulltitle | push: title %}