[simple] remove now superfluous help text

Fixes #498.

searx/templates/simple/categories.html

@@ -13,7 +13,6 @@
 }  -%}
 <div id="categories" class="search_categories {{categories_class}}">{{- '' -}}
     <div id="categories_container">
-        {%- if display_tooltip %}<div class="help">{{ _('Click on the magnifier to perform search') }}</div>{% endif -%}
         {%- for category in categories_as_tabs -%}
         <div class="category"><input type="checkbox" id="checkbox_{{ category|replace(' ', '_') }}" name="category_{{ category }}"{% if category in selected_categories %} checked="checked"{% endif %}/>
             <label for="checkbox_{{ category|replace(' ', '_') }}" class="tooltips">

searx/templates/simple/preferences.html

@@ -108,7 +108,6 @@
     {% if 'categories' not in locked_preferences %}
     <fieldset>
       <legend>{{ _('Default categories') }}</legend>
-      {% set display_tooltip = false %}
       {% include 'simple/categories.html' %}
     </fieldset>
     {% endif %}

searx/templates/simple/search.html

@@ -9,7 +9,6 @@
       <button id="clear_search" type="button" tabindex="-1"><span class="hide_if_nojs">{{ icon_big('close') }}</span><span class="show_if_nojs">{{ _('clear') }}</span></button>
       <button id="send_search" type="submit" tabindex="-1"><span class="hide_if_nojs">{{ icon_big('search-outline') }}</span><span class="show_if_nojs">{{ _('search') }}</span></button>
     </div>
-    {% set display_tooltip = true %}
     {% with categories_class='search-tabs' %}
       {% include 'simple/categories.html' %}
     {% endwith %}