Added button to example.html to toggle ng-center-anchor
Added button to example.html to toggle ng-center-anchor

gspinella/ngDraggable,beatboxjs/ngDraggable,dietrich-stein/ngDraggableRedux,JIakki/ngDraggable,octaviandavid/ngDraggable,dietrich-stein/ngDraggableRedux,LSEducation/ngDraggable,gspinella/ngDraggable,minioak/ngDraggable,YellowSharkMT/ngDraggable,akveo/ngDraggable,lucaspenney/ngDraggable,brunokindt/ngDraggable,brunokindt/ngDraggable,minioak/ngDraggable,LSEducation/ngDraggable,endiny/ngDraggable,YellowSharkMT/ngDraggable,beatboxjs/ngDraggable,paschty/ngDraggable,OdenFrey/ngDraggable,OdenFrey/ngDraggable,JIakki/ngDraggable,lucaspenney/ngDraggable,fatlinesofcode/ngDraggable,octaviandavid/ngDraggable,fatlinesofcode/ngDraggable,magnet-clip/ngDraggable,paschty/ngDraggable,Gmulti/ngDraggable,akveo/ngDraggable,endiny/ngDraggable,Gmulti/ngDraggable,magnet-clip/ngDraggable