update search panel for online documentation

doc/_themes/blue/searchbox.html

@@ -9,10 +9,9 @@
 #}
 {%- if pagename != "search" %}
 <div id="searchbox" style="display: none">
-  <h3>{{ _('Quick search') }}</h3>
-    <form class="search" action="{{ pathto('search') }}" method="get">
+      <form class="search" action="{{ pathto('search') }}" method="get">
       <input type="text" name="q" size="18" />
-      <input type="submit" value="{{ _('Go') }}" />
+      <input type="submit" value="{{ _('Search') }}" />
       <input type="hidden" name="check_keywords" value="yes" />
       <input type="hidden" name="area" value="default" />
       </p>