Remove trailing space.

Author: gkellogg

lib/frame.js

@@ -256,7 +256,7 @@ api.frame = (state, subjects, frame, parent, property = null) => {
             output['@reverse'] = output['@reverse'] || {};
             util.addValue(output['@reverse'], reverseProp, [], {propertyIsArray: true});
             api.frame(state, [subject], subframe, output['@reverse'][reverseProp], property);
-          } 
+          }
         }
       }
     }