adds in the .reset type of action to the x module capa styling

common/lib/xmodule/xmodule/css/capa/display.scss

@@ -577,7 +577,7 @@ section.problem {
   section.action {
     margin-top: 20px;
 
-    .save, .check, .show {
+    .save, .check, .show, .reset {
       height: ($baseline*2);
       font-weight: 600;
       vertical-align: middle;