Increase padding between menu items a bit

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

app/assets/stylesheets/generic/sidebar.scss

@@ -42,7 +42,7 @@
     }
 
     a {
-      padding: 7px 15px;
+      padding: 8px 15px;
       font-size: 13px;
       line-height: 18px;
       color: $gray;