Adds possibility of specifying HTMLElement or jQuery object as target

[Hissvard]

One thing I felt missing from the lib was a way, like the title says, to specify an HTMLElement or jQuery object as a target - in a project, I found myself having to create unique ids via uuids in order to target the toasts to a big number of dynamic elements.

This functionality would avoid that.

I took the liberty of also adding the support for jQuery objects - I've seen other libraries do it too as an extra service, but if you believe it might give the wrong idea that the library depends on jQuery to users it might be better to remove it.

One thing: You'll notice I only uploaded the updated dist/css/iziToast.min.css and dist/css/iziToast.min.js files - I ran the gulp command but only the minified versions were built. I've sadly barely used gulp so I'd like to know what I did wrong so I can fix this.