Update imagesLoaded from v2.1.0 to v3.0.4

I downloaded the uncompressed script from the official [imagesLoaded Github repo](https://github.com/desandro/imagesloaded/blob/master/imagesloaded.js).

The minified source was downloaded from the packaged script on: [desandro.github.io/imagesloaded/](http://desandro.github.io/imagesloaded/)

These files were taken from the v3.0.4 tag.