Fixed whois + added help

src/commands/help.js

@@ -0,0 +1,15 @@
+module.exports = function(bot, msg) {
+  const chatId = msg.chat.id;
+  const userName = msg.from.first_name;
+  const userId = msg.from.id;
+
+  const message = `Hi! I am Lynx!\nI am a simple bot made entirely from scratch in Node.js by Lucas Gabriel (lucmsilva).\n\nSome commands to test:
+  - /start: start the bot
+  - /help: send this message
+  - /whois: send some information about yourself\n\nSee my source code in:
+  https://github.com/lucmsilva651/lynx.\n\nThanks to all users, testers, contributors, and others. Without you, perhaps this bot wouldn't be possible.`;
+  
+  bot.sendMessage(chatId, message)
+    .catch(error => console.error('ERROR: Message cannot be send:', error));
+  console.log(`INFO: /help executed by ${userName}, ${userId}`);
+}