Progress Button Microinteractions with VueJS

I rewritten the Javascript source code, from using jQuery library into using VueJS framework.

Also I made it into a component, so this may be reused easily.

There is few changes in CSS, specially in transition. Then in Javascript, I changed some of the logic for changing the classes, and animations.

This is also a good opportunity for me to learn/practice the $emit, callback, and $refs of VueJS.

Quoted from old description: "Recently, I've been interested more in studying microinteraction, so I made an example button for uploading with microinteraction."

Here is the link for the old pen: https://codepen.io/takaneichinose/pen/KjBBOZ