Added ability for users who don't want to always disable the submit b…

…utton, to display all the errors in the form upon the user interacting with the submit button. (#459)

addon/components/paper-form.js

@@ -25,8 +25,12 @@ export default Component.extend(ParentMixin, {
       }
     },
     onSubmit() {
-      this.sendAction('onSubmit');
-      this.get('childComponents').setEach('isTouched', false);
+      if (this.get('isInvalid')) {
+        this.get('childComponents').setEach('isTouched', true);
+      } else {
+        this.sendAction('onSubmit');
+        this.get('childComponents').setEach('isTouched', false);
+      }
     }
   }
 });