title: Error: Property 'getConnection' does not exist on type 'Bluebird<Pool>'
body: <p>I need help, trying to make a connection to the MySQL database with .createPool tells me this error:</p>
  
  <p><strong>Property 'getConnection' does not exist on type 'Bluebird'. Did you forget to use 'await'?</strong></p>
  
  <p>I tried it a few months ago and everything went perfectly :/. 
  I think that in version 3 of promise-mysql there were some changes.
  I'm using typescript and I try to perform a rest API</p>
  
  <p>Use "promise-mysql": "^4.0.4", ES6, </p>
  
  <pre><code>`import mysql from 'promise-mysql';
  
  import keys from './keys';
  
  const pool = mysql.createPool(keys.database);
  
  pool.getConnection()
      .then((connection: any) =&gt; {
          pool.releaseConnection(connection);
          console.log('DB is connected');
      });
  export default pool;`
  </code></pre>