docs(README): update browser example to resolve images (#360)

Author: misa-coder

README.md

@@ -55,10 +55,10 @@ new CanvasConstructor.Canvas(canvasElement)
 Now, let's suppose we want to add images, we'll use `Canvas.resolveImage`, which works in both Node.js and browser:
 
 ```js
-const { Canvas } = require('canvas-constructor');
+const { Canvas, resolveImage } = require('canvas-constructor');
 
 async function createCanvas() {
-    const image = await Canvas.resolveImage('./images/kitten.png');
+    const image = await resolveImage('./images/kitten.png');
 
     return new Canvas(300, 400)
         .printImage(image, 0, 0, 300, 400)