Constructor
new Constructor()
Example
```
const Horloge = require('horloge');
// Using an async function so we can use await
(async () => {
const delay = duration =>
new Promise(resolve => setTimeout(resolve, duration));
let t = new Horloge();
t.start();
await delay(1000);
t.stop();
t.log(); // Timer took ~1000 ms
})();
```