Add imageSource option to native JS

[OleVik]

Following #41, adds imageSource as an option to override the href-attribute for source.

[nicolas-t]

Thanks :)

I prefer the name imageSourceAttribute, can you apply the changes and rebuild ?
Also can you write a test ?
I'll update the documenation

Thanks

[OleVik]

The repo isn't quite compatible with Windows, so I can't compile or test without changing a lot. It's been a while since I wrote tests, but I'd think it would be something akin to:

describe('Image source and attributes', function() {
  before(function() {
    chocolat = Chocolat(document.querySelectorAll('#example1 .chocolat-image'), {})
  })
  it('Should use the preferred attribute as a source', function() {})
})

And in index.html add an attribute like alternative="../demo/demo-images/1920x1080.png" to verify against.

[nicolas-t]

Thanks, released in v1.1.2
https://www.npmjs.com/package/chocolat?activeTab=versions