Updated instructions spacing

Author: SunJieMing

src/arrays.js

@@ -34,6 +34,7 @@ const filter = (elements, cb) => {
 };
 
 /* Extra Credit */
+
 const flatten = (elements) => {
   // Flattens a nested array (the nesting can be to any depth).
   // Example: flatten([1, [2], [3, [[4]]]]); => [1, 2, 3, 4];

src/closure.js

@@ -19,6 +19,7 @@ const limitFunctionCallCount = (cb, n) => {
 };
 
 /* Extra Credit */
+
 const cacheFunction = (cb) => {
   // Should return a funciton that invokes `cb`.
   // A cache (object) should be kept in closure scope.