Merge pull request #944 from kvch/fix-google-images

[fix] fix xpath of google images

searx/engines/google_images.py

     for result in dom.xpath('//div[@data-ved]'):
 
         try:
-            metadata = loads(''.join(result.xpath('./div[@class="rg_meta"]/text()')))
+            metadata = loads(''.join(result.xpath('./div[contains(@class, "rg_meta")]/text()')))
         except:
             continue