theme: oscar - add accesskey to input tags

l - language field
s - search field
t - time range field

The way to activate the accesskey depends on the browser and its platform [1]

[1] https://developer.mozilla.org/en-US/docs/Web/HTML/Global_attributes/accesskey

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>

searx/templates/oscar/languages.html

@@ -1,4 +1,4 @@
-<select class="language custom-select form-control" id="language" name="language">
+<select class="language custom-select form-control" id="language" name="language" accesskey="l">
   <option value="all" {% if current_language == 'all' %}selected="selected"{% endif %}>{{ _('Default language') }}</option>
 {%- for lang_id,lang_name,country_name,english_name in language_codes | sort(attribute=1) -%}
   <option value="{{ lang_id }}" {% if lang_id == current_language %}selected="selected"{% endif %}>

searx/templates/oscar/search.html

@@ -3,7 +3,7 @@
   <div class="row">
     <div class="col-xs-12 col-md-8">
       <div class="input-group search-margin">
-        <input type="search" name="q" class="form-control" id="q" placeholder="{{ _('Search for...') }}" aria-label="{{ _('Search for...') }}" autocomplete="off" value="{{ q }}">
+        <input type="search" name="q" class="form-control" id="q" placeholder="{{ _('Search for...') }}" aria-label="{{ _('Search for...') }}" autocomplete="off" value="{{ q }}" accesskey="s">
         <span class="input-group-btn">
             <button type="submit" class="btn btn-default" aria-label="{{ _('Start search') }}"><span class="hide_if_nojs">{{ icon('search') }}</span><span class="hidden active_if_nojs">{{ _('Start search') }}</span></button>
         </span>

searx/templates/oscar/search_full.html

@@ -6,7 +6,7 @@
     {% else %}
     <div class="input-group col-md-8 col-md-offset-2">
     {% endif %}
-        <input type="search" name="q" class="form-control input-lg autofocus" id="q" placeholder="{{ _('Search for...') }}" aria-label="{{ _('Search for...') }}" autocomplete="off" value="{{ q }}">
+        <input type="search" name="q" class="form-control input-lg autofocus" id="q" placeholder="{{ _('Search for...') }}" aria-label="{{ _('Search for...') }}" autocomplete="off" value="{{ q }}" accesskey="s">
         <span class="input-group-btn">
             <button type="submit" class="btn btn-default input-lg" aria-label="{{ _('Start search') }}"><span class="hide_if_nojs">{{ icon('search') }}</span><span class="hidden active_if_nojs">{{ _('Start search') }}</span></button>
         </span>

searx/templates/oscar/time-range.html

@@ -1,4 +1,4 @@
-<select name="time_range" id="time-range" class="custom-select form-control">{{- "" -}}
+<select name="time_range" id="time-range" class="custom-select form-control" accesskey="t">{{- "" -}}
     <option id="time-range-anytime" value="" {{ "selected" if time_range=="" or not time_range  else ""}}>
         {{- _('Anytime') -}}
     </option>{{- "" -}}