Fix examples

Author: tshemsedinov

JavaScript/2-sync-tuple.js

@@ -1,12 +1,12 @@
 'use strict';
 
-function fn(a, b) {
+function sum(a, b) {
   if (typeof(a) === 'number' && typeof(b) === 'number') {
     return [null, a + b];
   } else {
     return [new Error('a and b should be numbers')];
   }
 }
 
-console.log(fn(2, 3));
-console.log(fn(7, 'A'));
+console.log(sum(2, 3));
+console.log(sum(7, 'A'));

JavaScript/3-async.js

@@ -1,22 +1,22 @@
 'use strict';
 
-function fn2(a, b, callback) {
+function sum(a, b, callback) {
   if (typeof(a) === 'number' && typeof(b) === 'number') {
     callback(null, a + b);
   } else {
     callback(new Error('a and b should be numbers'));
   }
 }
 
-fn2(2, 3, (err, result) => {
+sum(2, 3, (err, result) => {
   if (err) {
     console.log(err.message);
     return;
   }
   console.log(result);
 });
 
-fn2(7, 'A', (err, result) => {
+sum(7, 'A', (err, result) => {
   if (err) {
     console.log(err.message);
     return;