Merge branch 'hide_profile_activity_on_mobile' into 'master'

Hide user profile activity graph on mobile

closes #14507 

## Before
![Screen_Shot_2016-03-26_at_10.28.21_PM](/uploads/5d5e2f77de936c2f2cd8a95132720a81/Screen_Shot_2016-03-26_at_10.28.21_PM.png)

## After
![Screen_Shot_2016-03-26_at_10.27.01_PM](/uploads/c011497b31368a0b7aa7d851541ac301/Screen_Shot_2016-03-26_at_10.27.01_PM.png)

## Medium width screen
![fix2](/uploads/2a5eb2d01f1a516991cd3e2b35b8aadc/fix2.gif)

See merge request !3412

app/assets/stylesheets/framework/calendar.scss

+.calender-block {
+  @media (min-width: $screen-sm-min) and (max-width: $screen-lg-min) {
+    overflow-x: scroll;
+  }
+}
+
 .user-calendar-activities {
   .calendar_onclick_hr {
     padding: 0;

app/views/users/show.html.haml

@@ -87,7 +87,7 @@
   %div{ class: container_class }
     .tab-content
       #activity.tab-pane
-        .gray-content-block.white.second-block
+        .gray-content-block.calender-block.white.second-block.hidden-xs
           %div{ class: container_class }
             .user-calendar{data: {href: user_calendar_path}}
               %h4.center.light