feat(random): Add ability to get an array of random Harry Potter names

If you pass a number to the random function, you will receive an array with that number of random
items

closes #2

src/index.js

@@ -1,8 +1,21 @@
 const
 uniqueRandomArray = require('unique-random-array'),
-harryPotterNames = require('./harry-potter-names.json');
+harryPotterNames = require('./harry-potter-names.json'),
+getRandomItem = uniqueRandomArray(harryPotterNames);
 
 module.exports = {
   all: harryPotterNames,
-  random: uniqueRandomArray(harryPotterNames)
+  random: random
 };
+
+function random (number) {
+  if(number === undefined) {
+    return getRandomItem();
+  } else {
+    let randomItems = [];
+    for (var i = 0; i < number; i++) {
+      randomItems.push(getRandomItem());
+    }
+    return randomItems;
+  }
+}

src/index.test.js

@@ -27,5 +27,13 @@ describe('Harry Potter names', function() {
 
       expect(harryPotterNames.all).to.include(randomItem);
     });
+
+    it('should return a random array of random items if passed a number', function() {
+      let randomItems = harryPotterNames.random(3);
+      expect(randomItems).to.have.lengthOf(3);
+      randomItems.forEach(item => {
+        expect(harryPotterNames.all).to.include(item);
+      });
+    });
   });
 });