Fixing `data-width` implementation.
Fixing `data-width` implementation.

`data-width` should be copied only if set.

BBC-News/Imager.js,hellopath/Imager.js,drummerboof/Imager.js,Brunosky75/Imager,kendrick-k/Imager.js,vidyar/Imager.js,icoee/Imager.js,tolis-e/Imager.js,vidyar/Imager.js,drummerboof/Imager.js,tolis-e/Imager.js,hellopath/Imager.js,kendrick-k/Imager.js,Brunosky75/Imager,icoee/Imager.js