Merge branch 'master' into master

requirements.txt

 certifi==2017.11.5
-flask==0.12.2
+flask==1.0.2
 flask-babel==0.11.2
-lxml==4.1.1
-idna==2.5
+lxml==4.2.1
+idna==2.6
 pygments==2.1.3
-pyopenssl==17.4.0
-python-dateutil==2.6.1
+pyopenssl==18.0.0
+python-dateutil==2.7.3
 pyyaml==3.12
 requests[socks]==2.18.4

searx/settings.yml

     engine : xpath
     paging : True
     search_url : https://scholar.google.com/scholar?start={pageno}&q={query}&hl=en&as_sdt=0,5&as_vis=1
-    results_xpath : //div[@class="gs_r"]/div[@class="gs_ri"]
+    results_xpath : //div[contains(@class, "gs_r")]/div[@class="gs_ri"]
     url_xpath : .//h3/a/@href
     title_xpath : .//h3/a
     content_xpath : .//div[@class="gs_rs"]

searx/static/themes/oscar/less/logicodev/search.less

     padding-bottom: 0.4rem;
     padding-top: 0.4rem;
     text-align: center;
+    min-width: 50px;
   }
   label:last-child, .input-group-addon:last-child {
       border-right: @mild-gray 1px solid;

searx/static/themes/oscar/less/pointhi/search.less

         padding-bottom: 0.8rem;
         padding-top: 0.8rem;
         text-align: center;
+        min-width: 50px;
     }
 
     label:last-child, .input-group-addon:last-child {