[mod] bing and duckduckgo engines : add / rename locale parameter

engines.cfg_sample

 
 [bing]
 engine = bing
-language = en-us
+locale = en-us
 
 [cc]
 engine=currency_convert
 
 [duckduckgo]
 engine = duckduckgo
+locale = en-us
 
 [flickr]
 engine = flickr

searx/engines/bing.py

 
 base_url = 'http://www.bing.com/'
 search_string = 'search?{query}'
-language = 'en-us' # see http://msdn.microsoft.com/en-us/library/dd251064.aspx
+locale = 'en-US' # see http://msdn.microsoft.com/en-us/library/dd251064.aspx
 
 
 def request(query, params):
-    search_path = search_string.format(query=urlencode({'q': query, 'setmkt': language}))
+    search_path = search_string.format(query=urlencode({'q': query, 'setmkt': locale}))
     #if params['category'] == 'images':
     #    params['url'] = base_url + 'images/' + search_path
     params['url'] = base_url + search_path

searx/engines/duckduckgo.py

 from searx.utils import html_to_text
 
 url = 'https://duckduckgo.com/'
-search_url = url + 'd.js?{query}&l=us-en&p=1&s=0'
+search_url = url + 'd.js?{query}&p=1&s=0'
+locale = 'us-en'
 
 def request(query, params):
-    params['url'] = search_url.format(query=urlencode({'q': query}))
+    params['url'] = search_url.format(query=urlencode({'q': query, 'l': locale}))
     return params