Update description

searx/tests/test_webapp.py

     def test_opensearch_xml(self):
         result = self.app.get('/opensearch.xml')
         self.assertEqual(result.status_code, 200)
-        self.assertIn('<Description>Search searx</Description>', result.data)
+        self.assertIn('<Description>a privacy-respecting, hackable metasearch engine</Description>', result.data)
 
     def test_favicon(self):
         result = self.app.get('/favicon.ico')