Update pie.html
Update pie.html

use cdn as per https://github.com/dc-js/dc.js/issues/616#issuecomment-46032360
lfarrell/angular-dc,smee/angular-dc,Pinqvin/angular-dc,BoldData/angular-dc,TomNeyland/angular-dc,BoldData/angular-dc,NateEichenlaub/angular-dc,Pinqvin/angular-dc,TomNeyland/angular-dc,NateEichenlaub/angular-dc,motin/angular-dc,smee/angular-dc