[enh] settings option to change instance name - closes #450

searx/settings.yml

 general:
     debug : False # Debug mode, only for development
+    instance_name : "searx" # displayed name
 
 search:
     safe_search : 0 # Filter results. 0: None, 1: Moderate, 2: Strict

searx/templates/courgette/opensearch.xml

 <?xml version="1.0" encoding="utf-8"?>
 <OpenSearchDescription xmlns="http://a9.com/-/spec/opensearch/1.1/">
-  <ShortName>searx</ShortName>
+  <ShortName>{{ instance_name }}</ShortName>
   <Description>a privacy-respecting, hackable metasearch engine</Description>
   <InputEncoding>UTF-8</InputEncoding>
   <Image>{{ host }}{{ url_for('static', filename='img/favicon.png') | replace("/", "", 1) }}</Image>

searx/templates/default/opensearch.xml

 <?xml version="1.0" encoding="utf-8"?>
 <OpenSearchDescription xmlns="http://a9.com/-/spec/opensearch/1.1/">
-  <ShortName>searx</ShortName>
+  <ShortName>{{ instance_name }}</ShortName>
   <Description>a privacy-respecting, hackable metasearch engine</Description>
   <InputEncoding>UTF-8</InputEncoding>
   <Image>{{ host }}{{ url_for('static', filename='img/favicon.png') | replace("/", "", 1) }}</Image>

searx/templates/oscar/base.html

     <meta name="referrer" content="no-referrer">
     <meta name="viewport" content="width=device-width, initial-scale=1 , maximum-scale=1.0, user-scalable=1" />
     {% block meta %}{% endblock %}
-    <title>{% block title %}{% endblock %}searx</title>
+    <title>{% block title %}{% endblock %}{{ instance_name }}</title>
 
     <link rel="stylesheet" href="{{ url_for('static', filename='css/bootstrap.min.css') }}" type="text/css" />
     <link rel="stylesheet" href="{{ url_for('static', filename='css/oscar.min.css') }}" type="text/css" />
     {% block head %}
     {% endblock %}
 
-    <link title="searx" type="application/opensearchdescription+xml" rel="search" href="{{ url_for('opensearch') }}"/>
+    <link title="{{ instance_name }}" type="application/opensearchdescription+xml" rel="search" href="{{ url_for('opensearch') }}"/>
 
     <script type="text/javascript">
         searx = {};

searx/templates/oscar/navbar.html

                 <span class="icon-bar"></span>
                 <span class="icon-bar"></span>
             </button>
-            <a class="navbar-brand" href="{{ url_for('index') }}">searx</a>
+            <a class="navbar-brand" href="{{ url_for('index') }}">{{ instance_name }}</a>
         </div>
         {% else %}
         <div class="navbar-header">
                 <span class="icon-bar"></span>
                 <span class="icon-bar"></span>
             </button>
-            <a class="navbar-brand" href="{{ url_for('index') }}">searx</a>
+            <a class="navbar-brand" href="{{ url_for('index') }}">{{ instance_name }}</a>
         </div>
         <div class="navbar-collapse collapse">
             <ul class="nav navbar-nav navbar-right"> <!-- results.html -->

searx/templates/oscar/opensearch.xml

 <?xml version="1.0" encoding="utf-8"?>
 <OpenSearchDescription xmlns="http://a9.com/-/spec/opensearch/1.1/">
-  <ShortName>searx</ShortName>
+  <ShortName>{{ instance_name }}</ShortName>
   <Description>a privacy-respecting, hackable metasearch engine</Description>
   <InputEncoding>UTF-8</InputEncoding>
   <Image>{{ host }}{{ url_for('static', filename='img/favicon.png') | replace("/", "", 1) }}</Image>

searx/webapp.py

 
     kwargs['cookies'] = request.cookies
 
+    kwargs['instance_name'] = settings['general']['instance_name']
+
     kwargs['scripts'] = set()
     for plugin in request.user_plugins:
         for script in plugin.js_dependencies: