fixes typo on rendering-with-helpers guide
fixes typo on rendering-with-helpers guide

cyberkoi/website,raycohen/website,zeppelin/emberjs-website,jimmay5469/website,mrjavascript/website,josemarluedke/ember-website,workmanw/ember-website,bmac/website,wifelette/website,Nick-Cotter/aboutme,mrjavascript/website,tmock12/website,duggiefresh/website,AaronSikes/website,josemarluedke/ember-website,raycohen/website,MinxianLi/ember,datajohnny/website,martndemus/website,balupton/ember-website,SaladFork/emberjs-website,AaronSikes/website,kkenan/website,wifelette/website,praxxis/website,duggiefresh/website,AgilionApps/website,workmanw/ember-website,cllns/emberjs-website,MinxianLi/ember,ktornwall/website,zeppelin/emberjs-website,bmac/website,shearwater-intl/website,praxxis/website,maxcal/website,datajohnny/website,cllns/emberjs-website,bmac/website,Eric-Guo/website,duggiefresh/website,MinxianLi/ember,cllns/emberjs-website,raycohen/website,elidupuis/website,SaladFork/emberjs-website,EricSchank/website,maxcal/website,josemarluedke/ember-website,zeppelin/emberjs-website,davidpett/website,greyhwndz/website,quangv/website,jimmay5469/website,maczniak/emberjs,Eric-Guo/website,AaronSikes/website,workmanw/ember-website,AgilionApps/website,elwayman02/website,kpfefferle/website,wifelette/website,elwayman02/website,mrjavascript/website,datajohnny/website,shama/website,shearwater-intl/website,Nick-Cotter/aboutme,EricSchank/website,kpfefferle/website,jimmay5469/website,elidupuis/website,kkenan/website,shearwater-intl/website,knownasilya/website,koriroys/emberjs-website,quangv/website,rwjblue/website,rwjblue/website,balupton/ember-website,josemarluedke/ember-website,maczniak/emberjs,cyberkoi/website,davidpett/website,martndemus/website,kkenan/website,workmanw/ember-website,tmock12/website,greyhwndz/website,bmac/website,SaladFork/emberjs-website,koriroys/emberjs-website,ktornwall/website,greyhwndz/website,elidupuis/website,AgilionApps/website,quangv/website,tmock12/website,EricSchank/website,ktornwall/website,koriroys/emberjs-website,SaladFork/emberjs-website,martndemus/website,zeppelin/emberjs-website,shama/website,davidpett/website,maxcal/website,balupton/ember-website,knownasilya/website,Eric-Guo/website,kpfefferle/website,cyberkoi/website,elwayman02/website