title: pixi js: drag and drop circle
body: <p>I started to create simple js game using <a href="https://www.google.ru/url?sa=t&amp;rct=j&amp;q=&amp;esrc=s&amp;source=web&amp;cd=1&amp;ved=0ahUKEwjhsKCtgpbMAhWjQJoKHdUhA-0QFggbMAA&amp;url=http%3A%2F%2Fwww.pixijs.com%2F&amp;usg=AFQjCNFczp7PxTX24cVaRoVCbzouLzs4ag&amp;sig2=uSPDkzzMjiJVKLFmLZUAnw&amp;bvm=bv.119745492,d.bGs" rel="noreferrer">pixijs</a>. I need drag'n'drop functionality for Graphics circle but can't find info for this. I see only <a href="http://pixijs.github.io/examples/index.html?s=demos&amp;f=dragging.js&amp;title=Dragging" rel="noreferrer">this example</a> with sprites.</p>