[fix] brands: add variables from build env to jinja templating

We have some variables in the build environment which are also needed in the
templating process.  Theses variables are relavant if one creates a fork with
its own branding.  We treat these variables under the term 'brands'.

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

searx/webapp.py

@@ -57,6 +57,7 @@ from babel.support import Translations
 import flask_babel
 from flask_babel import Babel, gettext, format_date, format_decimal
 from flask.json import jsonify
+from searx import brand
 from searx import settings, searx_dir, searx_debug
 from searx.exceptions import SearxParameterException
 from searx.engines import (
@@ -427,6 +428,8 @@ def render(template_name, override_theme=None, **kwargs):
 
     kwargs['preferences'] = request.preferences
 
+    kwargs['brand'] = brand
+
     kwargs['scripts'] = set()
     for plugin in request.user_plugins:
         for script in plugin.js_dependencies: